EXHIBIT 4.1



















                           IRON MOUNTAIN INCORPORATED

                                       TO

                            ------------------------

                                     Trustee




                                    Indenture

                          Dated as of __________, 199_



                             Senior Debt Securities




                                     







                                                TABLE OF CONTENTS1

                                                                                                               PAGE

                                                                                                              
         PARTIES..................................................................................................1

         RECITALS.................................................................................................1


                                                    ARTICLE ONE

                              DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

         SECTION 101.  Definitions................................................................................2
                           "Act"    ..............................................................................2
                           "Additional Amounts"...................................................................3
                           "Affiliate"............................................................................3
                           "Authenticating Agent".................................................................3
                           "Authorized Newspaper".................................................................3
                           "Bankruptcy Law".......................................................................3
                           "Bearer Security"......................................................................3
                           "Board"  ..............................................................................3
                           "Board Resolution".....................................................................3
                           "Business Day".........................................................................3
                           "CEDEL"  ..............................................................................3
                           "Commission"...........................................................................3
                           "Common Depositary"....................................................................3
                           "Company"..............................................................................3
                           "Company Request" and "Company Order"..................................................3
                           "Conversion Event".....................................................................4
                           "Corporate Trust Office"...............................................................4
                           "corporation"..........................................................................4
                           "coupon" ..............................................................................4
                           "Custodian"............................................................................4
                           "Declaration"..........................................................................4
                           "Defaulted Interest"...................................................................4
                           "Dollar" or "$"........................................................................4
                           "DTC"    ..............................................................................4
                           "ECU"    ..............................................................................4
                           "Euroclear"............................................................................4
                           "European Communities".................................................................4
                           "European Monetary System".............................................................4
                           "Event of Default".....................................................................4
                           "Exchange Date"........................................................................4
                           "Foreign Currency".....................................................................4
                           "Funds from Operations"................................................................4
                           "GAAP"   ..............................................................................5
                           "Government Obligations"...............................................................5
                           "Holder" ..............................................................................5
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1        This Table of Contents shall not, for any purpose, be deemed to be part of this Indenture.

                                                        





                           "Indenture"............................................................................5
                           "Indexed Security".....................................................................5
                           "interest".............................................................................5
                           "Interest Payment Date"................................................................5
                           "Maturity".............................................................................5
                           "Officers' Certificate"................................................................5
                           "Opinion of Counsel"...................................................................5
                           "Original Issue Discount Security".....................................................6
                           "Outstanding"..........................................................................6
                           "Paying Agent".........................................................................6
                           "Person" ..............................................................................7
                           "Place of Payment".....................................................................7
                           "Predecessor Security".................................................................7
                           "Redemption Date"......................................................................7
                           "Redemption Price".....................................................................7
                           "Registered Security"..................................................................7
                           "Regular Record Date"..................................................................7
                           "Repayment Date".......................................................................7
                           "Responsible Officer"..................................................................7
                           "Security".............................................................................7
                           "Security Register" and "Security Registrar"...........................................7
                           "Significant Subsidiary"...............................................................7
                           "Special Record Date"..................................................................8
                           "Stated Maturity"......................................................................8
                           "Subsidiary"...........................................................................8
                           "Trust Indenture Act" or "TIA".........................................................8
                           "Trustee"..............................................................................8
                           "United States"........................................................................8
                           "United States person".................................................................8
                           "Yield to Maturity"....................................................................8
         SECTION 102.  Compliance Certificates and Opinions.......................................................8
         SECTION 103.  Form of Documents Delivered to Trustee.....................................................9
         SECTION 104.  Acts of Holders............................................................................9
         SECTION 105.  Notices, etc., to Trustee and Company.....................................................10
         SECTION 106.  Notice to Holders; Waiver.................................................................10
         SECTION 107.  Effect of Headings and Table of Contents..................................................11
         SECTION 108.  Successors and Assigns....................................................................11
         SECTION 109.  Separability Clause.......................................................................11
         SECTION 110.  Benefits of Indenture.....................................................................11
         SECTION 111.  Governing Law.............................................................................11
         SECTION 112.  Legal Holidays............................................................................12

                                                    ARTICLE TWO

                                                 SECURITIES FORMS

         SECTION 201.  Forms of Securities.......................................................................12
         SECTION 202.  Form of Trustee's Certificate of Authentication...........................................12
         SECTION 203.  Securities Issuable in Global Form........................................................12


                                                       -ii-





                                                   ARTICLE THREE

                                                  THE SECURITIES

         SECTION 301.  Amount Unlimited; Issuable in Series......................................................13
         SECTION 302.  Denominations.............................................................................16
         SECTION 303.  Execution, Authentication, Delivery and Dating............................................16
         SECTION 304.  Temporary Securities......................................................................18
         SECTION 305.  Registration, Registration of Transfer and Exchange.......................................19
         SECTION 306.  Mutilated, Destroyed, Lost and Stolen Securities..........................................22
         SECTION 307.  Payment of Interest; Interest Rights Preserved............................................22
         SECTION 308.  Persons Deemed Owners.....................................................................24
         SECTION 309.  Cancellation..............................................................................24
         SECTION 310.  Computation of Interest...................................................................25

                                                   ARTICLE FOUR

                                            SATISFACTION AND DISCHARGE

         SECTION 401.  Satisfaction and Discharge of Indenture...................................................25
         SECTION 402.  Application of Trust Funds................................................................26

                                                   ARTICLE FIVE

                                                     REMEDIES

         SECTION 501.  Events of Default.........................................................................26
         SECTION 502.  Acceleration of Maturity; Rescission and Annulment........................................27
         SECTION 503.  Collection of Indebtedness and Suits for Enforcement by Trustee...........................28
         SECTION 504.  Trustee May File Proofs of Claim..........................................................29
         SECTION 505.  Trustee May Enforce Claims Without Possession of Securities or Coupons....................29
         SECTION 506.  Application of Money Collected............................................................30
         SECTION 507.  Limitation on Suits.......................................................................30
         SECTION 508.  Unconditional Right of Holders to Receive Principal, Premium, if any, Interest and
                           Additional Amounts....................................................................30
         SECTION 509.  Restoration of Rights and Remedies........................................................30
         SECTION 510.  Rights and Remedies Cumulative............................................................31
         SECTION 511.  Delay or Omission Not Waiver..............................................................31
         SECTION 512.  Control by Holders of Securities..........................................................31
         SECTION 513.  Waiver of Past Defaults...................................................................31
         SECTION 514.  Waiver of Usury, Stay or Extension Laws...................................................31
         SECTION 515.  Undertaking for Costs.....................................................................32

                                                    ARTICLE SIX

                                                    THE TRUSTEE

         SECTION 601.  Notice of Defaults........................................................................32
         SECTION 602.  Certain Rights of Trustee.................................................................32
         SECTION 603.  Not Responsible for Recitals or Issuance of Securities....................................33
         SECTION 604.  May Hold Securities.......................................................................33
         SECTION 605.  Money Held in Trust.......................................................................33

                                                       -iii-





         SECTION 606.  Compensation and Reimbursement............................................................33
         SECTION 607.  Corporate Trustee Required; Eligibility; Conflicting Interests............................34
         SECTION 608.  Resignation and Removal; Appointment of Successor.........................................34
         SECTION 609.  Acceptance of Appointment by Successor....................................................35
         SECTION 610.  Merger, Conversion, Consolidation or Succession to Business...............................36
         SECTION 611.  Appointment of Authentication Agent.......................................................36

                                                   ARTICLE SEVEN

                                 HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY

         SECTION 701.  Disclosure of Names and Addresses of Holders..............................................37
         SECTION 702.  Reports by Trustee........................................................................37
         SECTION 703.  Reports by Company........................................................................38
         SECTION 704.  Company to Furnish to Trustee Names and Addresses of Holders..............................38

                                                   ARTICLE EIGHT

                                       MERGER CONSOLIDATION, SALE OF ASSETS

         SECTION 801.  Consolidations and Mergers of Company and Sale of Assets..................................39
         SECTION 802.  Rights and Duties of Successor Corporation................................................39

                                                   ARTICLE NINE

                                              SUPPLEMENTAL INDENTURES

         SECTION 901.  Supplemental Indentures Without Consent of Holders........................................39
         SECTION 902.  Supplemental Indentures with Consent of Holders...........................................40
         SECTION 903.  Execution of Supplemental Indentures......................................................41
         SECTION 904.  Effect of Supplemental Indentures.........................................................41
         SECTION 905.  Conformity with Trust Indenture Act.......................................................41
         SECTION 906.  Reference in Securities to Supplemental Indentures........................................41

                                                    ARTICLE TEN

                                                     COVENANTS

         SECTION 1001.  Payment of Principal, Premium, if any, Interest and Additional Amounts...................42
         SECTION 1002.  Maintenance of Office or Agency..........................................................42
         SECTION 1003.  Money for Securities Payments to Be Held in Trust........................................43
         SECTION 1004.  Existence................................................................................44
         SECTION 1005.  Provision of Financial Information.......................................................44
         SECTION 1006.  Statement as to Compliance...............................................................44
         SECTION 1007.  Additional Amounts.......................................................................44
         SECTION 1008.  Waiver of Certain Covenants..............................................................45

                                                  ARTICLE ELEVEN

                                             REDEMPTION OF SECURITIES

         SECTION 1101.  Applicability of Article.................................................................45

                                                       -iv-





         SECTION 1102.  Election to Redeem; Notice to Trustee....................................................45
         SECTION 1103.  Selection by Trustee of Securities to Be Redeemed........................................46
         SECTION 1104.  Notice of Redemption.....................................................................46
         SECTION 1105.  Deposit of Redemption Price..............................................................47
         SECTION 1106.  Securities Payable on Redemption Date....................................................47
         SECTION 1107.  Securities Redeemed in Part..............................................................48

                                                  ARTICLE TWELVE

                                                   SINKING FUNDS

         SECTION 1201.  Applicability of Article.................................................................48
         SECTION 1202.  Satisfaction of Sinking Fund Payments with Securities....................................48
         SECTION 1203.  Redemption of Securities for Sinking Fund................................................48

                                                 ARTICLE THIRTEEN

                                        REPAYMENT AT THE OPTION OF HOLDERS

         SECTION  1301.  Applicability of Article................................................................49
         SECTION 1302.  Repayment of Securities..................................................................49
         SECTION 1303.  Exercise of Option.......................................................................49
         SECTION 1304.  When Securities Presented for Repayment Become Due and Payable...........................50
         SECTION 1305.  Securities Repaid in Part................................................................50

                                                 ARTICLE FOURTEEN

                                        DEFEASANCE AND COVENANT DEFEASANCE

         SECTION 1401.  Applicability of Article; Company's Option to Effect Defeasance or Covenant
                           Defeasance............................................................................50
         SECTION 1402.  Defeasance and Discharge.................................................................51
         SECTION 1403.  Covenant Defeasance......................................................................51
         SECTION 1404.  Conditions to Defeasance or Covenant Defeasance..........................................51
         SECTION 1405.  Deposited Money and Government Obligations to Be Held in Trust; Other
                           Miscellaneous Provisions..............................................................53

                                                  ARTICLE FIFTEEN

                                         MEETINGS OF HOLDERS OF SECURITIES

         SECTION 1501.  Purposes for Which Meetings May Be Called................................................53
         SECTION 1502.  Call, Notice and Place of Meetings.......................................................53
         SECTION 1503.  Persons Entitled to Vote at Meetings.....................................................54
         SECTION 1504.  Quorum; Action...........................................................................54
         SECTION 1505. Determination of Voting Rights; Conduct and Adjournment of Meetings.......................55
         SECTION 1506.  Counting Votes and Recording Action of Meetings..........................................55


         EXHIBIT A -- FORMS OF CERTIFICATION



                                                        -v-





                                            IRON MOUNTAIN INCORPORATED

         Reconciliation  and tie between Trust Indenture Act of 1939, as amended
(the "TIA"), and Indenture, dated as of __________, 199_.


               TIA Section                         Indenture Section
Sec. 310(a)(1)..........................                  607
        (a)(2)..........................                  607
        (b).............................               607, 608
Sec. 312(a).............................                  704
Sec. 312(c).............................                  701
Sec. 313(a).............................                  702
       (c)..............................                  702
Sec. 314(a).............................                 1005
       (a)(4)...........................                 1006
       (c)(1)...........................                  102
       (c)(2)...........................                  102
       (e)..............................                  102
Sec. 315(b).............................                  601
Sec. 316(a) (last sentence).............          101 ("Outstanding")
        (a)(1)(A).......................               502, 512
        (a)(1)(B).......................                  513
       (b)..............................                  508
Sec. 317(a)(1)..........................                  503
       (a)(2)...........................                  504
Sec. 318(a).............................                  111
       (c)..............................                  111

- -------------------

NOTE: This  reconciliation and tie shall not, for any purpose, be deemed to be a
part of the Indenture.

         Attention  should also be directed to Section  318(c) of the TIA, which
provides that the provisions of Sections 310 to and including 317 of the TIA are
a part of and  govern  every  qualified  indenture,  whether  or not  physically
contained therein.

                                                        






         INDENTURE,  dated  as  of  ___________,  199_,  between  IRON  MOUNTAIN
INCORPORATED, a Delaware Corporation (hereinafter called the "Company"),  having
its principal office at 745 Atlantic  Avenue,  Boston  Massachusetts  02111 and,
_____________________________,  a ___________, as Trustee hereunder (hereinafter
called  the   "Trustee"),   having  its  initial   Corporate   Trust  Office  at
_____________________________________.

                             RECITALS OF THE COMPANY

                           The Company  deems it necessary to issue from time to
time  for  lawful   purposes  its  debt  securities   (hereinafter   called  the
"Securities") evidencing its indebtedness, and has duly authorized the execution
and delivery of this  Indenture to provide for the issuance from time to time of
the Securities,  unlimited as to principal amount, to bear interest at the rates
or formulas,  to mature at such times and to have such other provisions as shall
be fixed as hereinafter provided.

                           This  Indenture is subject to the  provisions  of the
Trust Indenture Act of 1939, as amended, that are deemed to be incorporated into
this Indenture by such Act, and shall, to the extent applicable,  be governed by
such provisions.

                           All things  necessary to make this  Indenture a valid
agreement of the Company, in accordance with its terms, have been done.

                           NOW, THEREFORE, THIS INDENTURE WITNESSETH:

                           For  and in  consideration  of the  premises  and the
purchase of the Securities by the Holders thereof, it is mutually covenanted and
agreed, for the equal and proportionate benefit of all Holders of the Securities
or of a series thereof, as follows:

                                   ARTICLE ONE

             DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION

                 SECTION 101.  Definitions.  For all purposes of this Indenture,
except as otherwise expressly provided or unless the context otherwise requires:

                 (1)  the  terms  defined  in this  Article  have  the  meanings
assigned  to  them  in this  Article,  and  include  the  plural  as well as the
singular;

                 (2) all other terms used  herein  which are defined in the TIA,
either  directly or by reference  therein,  have the  meanings  assigned to them
therein, and the terms "cash transaction" and "self-liquidating  paper", as used
in TIA Section 311, shall have the meanings assigned to them in the rules of the
Commission adopted under the TIA;

                 (3) all accounting terms not otherwise  defined herein have the
meanings assigned to them in accordance with GAAP; and

                 (4) the words  "herein",  "hereof"  and  "hereunder"  and other
words of  similar  import  refer  to this  Indenture  as a whole  and not to any
particular Article, Section or other subdivision.

                 Certain terms, used principally in Article Three, Article Five,
Article Six and Article Ten, are defined in those Articles.

                 "Act",  when used with  respect to any Holder,  has the meaning
specified in Section 104.

                                                        





                 "Additional  Amounts"  means any  additional  amounts which are
required  by a  Security  or  by  or  pursuant  to  a  Board  Resolution,  under
circumstances specified therein, to be paid by the Company in respect of certain
taxes imposed on certain Holders and which are owing to such Holders.

                 "Affiliate"  of any  specified  Person  means any other  Person
directly or indirectly  controlling or controlled by or under direct or indirect
common control with such specified Person.  For the purposes of this definition,
"control"  when used with  respect to any  specified  Person  means the power to
direct the  management  and  policies of such  Person,  directly or  indirectly,
whether  through the ownership of voting  securities,  by contract or otherwise;
and the terms  "controlling" and "controlled"  have meanings  correlative to the
foregoing.

                 "Authenticating Agent" means any authenticating agent appointed
by the Trustee pursuant to Section 611.

                 "Authorized  Newspaper"  means  a  newspaper,  printed  in  the
English  language  or in an official  language  of the  country of  publication,
customarily  published  on  each  Business  Day,  whether  or not  published  on
Saturdays,  Sundays or  holidays,  and of general  circulation  in each place in
connection  with which the term is used or in the  financial  community  of each
such  place.  Whenever  successive  publications  are  required  to be  made  in
Authorized Newspapers, the successive publications may be made in the same or in
different  Authorized   Newspapers  in  the  same  city  meeting  the  foregoing
requirements and in each case on any Business Day.

                 "Bankruptcy Law" has the meaning specified in Section 501.

                 "Bearer  Security" means any Security  established  pursuant to
Section 201 which is payable to bearer.

                 "Board"  means the board of  directors  of the  Company  or any
committee of that board duly authorized to act hereunder.

                 "Board  Resolution"  means a copy of a resolution  certified by
the Secretary or an Assistant Secretary of the Company to have been duly adopted
by  the  Board  and  to be in  full  force  and  effect  on  the  date  of  such
certification, and delivered to the Trustee.

                 "Business  Day", when used with respect to any Place of Payment
or any  other  particular  location  referred  to in  this  Indenture  or in the
Securities,  means,  unless  otherwise  specified with respect to any Securities
pursuant  to Section  301,  any day,  other than a Saturday  or Sunday,  that is
neither a legal holiday nor a day on which banking institutions in that Place of
Payment or particular  location are authorized or required by law, regulation or
executive order to close.

                 "CEDEL" means Cedel, S.A., or its successor.

                 "Commission" means the Securities and Exchange  Commission,  as
from time to time  constituted,  created  under the  Securities  Exchange Act of
1934, or, if at any time after  execution of this  instrument such Commission is
not  existing  and  performing  the  duties now  assigned  to it under the Trust
Indenture Act, then the body performing such duties on such date.

                 "Common Depositary" has the meaning specified in Section 304.

                 "Company"  means the Person named as the "Company" in the first
paragraph of this Indenture until a successor shall have become such pursuant to
the applicable provisions of this Indenture, and thereafter "Company" shall mean
such successor.

                 "Company  Request" and "Company  Order" mean,  respectively,  a
written  request or order  signed in the name of the Company by the  Chairman of
the Board and Chief Executive Officer, the President or a Vice President, and 

                                       -2-





by its Chief Financial Officer, Treasurer, an Assistant Treasurer, the Secretary
or an Assistant Secretary, of the Company, and delivered to the Trustee.

                 "Conversion  Event" means the cessation of use of (i) a Foreign
Currency  both by the  government  of the country which issued such currency and
for the settlement of transactions by a central bank or other public institution
of or within the international  banking community,  (ii) the ECU both within the
European  Monetary  System  and for the  settlement  of  transactions  by public
institutions  of or within the European  Communities  or (iii) any currency unit
(or  composite  currency)  other than the ECU for the  purposes for which it was
established.

                 "Corporate  Trust  Office"  means the office of the  Trustee at
which, at any particular time, its corporate trust business shall be principally
administered, which office at the date hereof is located at _____________
________________________.

                 "corporation"  includes corporations,  associations,  companies
and business trusts.

                 "coupon"  means any interest  coupon  appertaining  to a Bearer
Security.

                 "Custodian" has the meaning specified in Section 501.

                 "Declaration" has the meaning specified in Section 113.

                 "Defaulted Interest" has the meaning specified in Section 307.

                 "Dollar" or "$" means a dollar or other equivalent unit in such
coin or currency  of the United  States of America as at the time shall be legal
tender for the payment of public and private debts.

                 "DTC" means The  Depository  Trust  Company,  or any  successor
thereto.

                 "ECU" means the European  Currency  Unit as defined and revised
from time to time by the Council of the European Communities.

                 "Euroclear"  means Morgan  Guaranty  Trust Company of New York,
Brussels Office, or its successor as operator of the Euroclear System.

                 "European  Communities" means the European Economic  Community,
the European Coal and Steel Community and the European Atomic Energy Community.

                 "European  Monetary System" means the European  Monetary System
established by the Resolution of December 5, 1978 of the Council of the European
Communities.

                 "Event of Default" has the meaning specified in Article Five.

                 "Exchange Date" has the meaning specified in Section 304.

                 "Foreign  Currency"  means  any  currency,   currency  unit  or
composite  currency,  including,  without  limitation,  the ECU,  issued  by the
government of one or more  countries  other than the United States of America or
by any recognized confederation or association of such governments.

                 "Funds from  Operations" for any period means the  consolidated
net income of the Company and its  Subsidiaries  for such period  without giving
effect to  depreciation  and  amortization,  gains or losses from  extraordinary
items,  gains or losses on sales of real estate,  gains or losses on investments
in marketable  securities  and any  

                                       -3-





provision/benefit  for income taxes for such period,  plus funds from operations
of  unconsolidated  joint  ventures,  all  determined  on a consistent  basis in
accordance with GAAP.

                 "GAAP" means generally accepted accounting principles in effect
from time to time as used in the United States applied on a consistent basis.

                 "Government  Obligations" means securities which are (i) direct
obligations of the United States of America or the  government  which issued the
Foreign Currency in which the Securities of a particular series are payable, for
the payment of which its full faith and credit is pledged or (ii) obligations of
a Person controlled or supervised by and acting as an agency or  instrumentality
of the United  States of America or such  government  which  issued the  Foreign
Currency  in which the  Securities  of such series are  payable,  the payment of
which is unconditionally guaranteed as a full faith and credit obligation by the
United States of America or such other  government,  which,  in either case, are
not callable or redeemable at the option of the issuer  thereof,  and shall also
include a depository receipt issued by a bank or trust company as custodian with
respect to any such Government  Obligation or a specific  payment of interest on
or principal of any such  Government  Obligation  held by such custodian for the
account of the holder of a depository receipt; provided that (except as required
by law) such  custodian is not  authorized to make any deduction from the amount
payable to the holder of such depository receipt from any amount received by the
custodian in respect of the  Government  Obligation  or the specific  payment of
interest  on or  principal  of  the  Government  Obligation  evidenced  by  such
depository receipt.

                 "Holder"  means,  in the  case of a  Registered  Security,  the
Person in whose name a Security is registered  in the Security  Register and, in
the case of a Bearer Security, the bearer thereof and, when used with respect to
any coupon, shall mean the bearer thereof.

                 "Indenture" means this instrument as originally  executed or as
it may from time to time be  supplemented  or amended by one or more  indentures
supplemental  hereto entered into pursuant to the applicable  provisions hereof,
and shall include the terms of particular  series of Securities  established  as
contemplated by Section 301; provided,  however,  that, if at any time more than
one Person is acting as Trustee under this instrument,  "Indenture"  shall mean,
with  respect to any one or more series of  Securities  for which such Person is
Trustee,  this instrument as originally  executed or as it may from time to time
be supplemented or amended by one or more applicable provisions hereof and shall
include the terms of the or those particular series of Securities for which such
Person is  Trustee  established  as  contemplated  by  Section  301,  exclusive,
however,  of any  provisions  or terms which  relate  solely to other  series of
Securities  for which such Person is Trustee,  regardless  of when such terms or
provisions  were adopted,  and  exclusive of any  provisions or terms adopted by
means of one or more indentures supplemental hereto executed and delivered after
such Person had become such Trustee but to which such Person,  as such  Trustee,
was not a party.

                 "Indexed  Security" means a Security the terms of which provide
that the principal amount thereof payable at Stated Maturity may be more or less
than the principal face amount thereof at original issuance.

                 "interest",  when  used  with  respect  to  an  Original  Issue
Discount  Security which by its terms bears interest only after Maturity,  shall
mean interest payable after Maturity,  and, when used with respect to a Security
which provides for the payment of Additional  Amounts  pursuant to Section 1007,
includes such Additional Amounts.

                 "Interest   Payment  Date",  when  used  with  respect  to  any
Security,  means the Stated  Maturity  of an  installment  of  interest  on such
Security.

                 "Maturity",  when used with respect to any Security,  means the
date on which the  principal  of such  Security or an  installment  of principal
becomes  due and  payable as therein or herein  provided,  whether at the Stated
Maturity or by declaration  of  acceleration,  notice of  redemption,  notice of
option to elect repayment or otherwise.


                                       -4-





                 "Officers'  Certificate"  means  a  certificate  signed  by the
Chairman of the Board and Chief Executive Officer, President or a Vice President
and by the Chief  Financial  Officer,  Treasurer,  an Assistant  Treasurer,  the
Secretary  or an  Assistant  Secretary  of the  Company,  and  delivered  to the
Trustee.

                 "Opinion of Counsel"  means a written  opinion of counsel,  who
may be counsel  for the  Company  (including  counsel  who is an employee of the
Company) and who shall be acceptable to the Trustee.

                 "Original  Issue  Discount  Security"  means any Security which
provides  for an amount  less than the  principal  amount  thereof to be due and
payable upon a declaration of acceleration of the Maturity  thereof  pursuant to
Section 502.

                 "Outstanding",  when used with respect to Securities, means, as
of the date of  determination,  all  Securities  theretofore  authenticated  and
delivered under this Indenture, except:

                 (i)  Securities   theretofore   cancelled  by  the  Trustee  or
delivered to the Trustee for cancellation;

                 (ii)  Securities,  or portions  thereof,  for whose  payment or
redemption  or  repayment  at the  option of the Holder  money in the  necessary
amount has been  theretofore  deposited  with the  Trustee  or any Paying  Agent
(other than the  Company) in trust or set aside and  segregated  in trust by the
Company  (if the Company  shall act as its own Paying  Agent) for the Holders of
such  Securities and any coupons  appertaining  thereto;  provided that, if such
Securities  are to be redeemed,  notice of such  redemption  has been duly given
pursuant to this Indenture or provision therefor satisfactory to the Trustee has
been made;

                 (iii)  Securities,  except to the extent  provided  in Sections
1402 and 1403, with respect to which the Company has effected  defeasance and/or
covenant defeasance as provided in Article Fourteen;

                 (iv) Securities which have been paid pursuant to Section 306 or
in exchange for or in lieu of which other Securities have been authenticated and
delivered pursuant to this Indenture,  other than any such Securities in respect
of which there shall have been presented to the Trustee proof satisfactory to it
that such  Securities  are held by a bona fide  purchaser  in whose  hands  such
Securities are valid obligations of the Company; and

                 (v) Securities  converted into Common Shares,  Preferred Shares
or other  securities  of the  Company  pursuant  to or in  accordance  with this
Indenture if the terms of such Securities provide for convertibility pursuant to
Section 301;

provided,  however,  that in  determining  whether the Holders of the  requisite
principal amount of the Outstanding  Securities have given any request,  demand,
authorization,  direction, notice, consent or waiver hereunder or are present at
a meeting of  Holders  for quorum  purposes,  and for the  purpose of making the
calculations  required  by TIA  Section  313,  (i) the  principal  amount  of an
Original   Issue   Discount   Security  that  may  be  counted  in  making  such
determination or calculation and that shall be deemed to be Outstanding for such
purpose  shall be equal to the  amount of  principal  thereof  that would be (or
shall  have  been  declared  to be)  due  and  payable,  at  the  time  of  such
determination,  upon a  declaration  of  acceleration  of the  maturity  thereof
pursuant to Section 502, (ii) the principal  amount of any Security  denominated
in a Foreign  Currency  that may be  counted  in making  such  determination  or
calculation and that shall be deemed Outstanding for such purpose shall be equal
to the Dollar equivalent, determined pursuant to Section 301 as of the date such
Security is originally  issued by the Company,  of the principal  amount (or, in
the case of an Original Issue  Discount  Security,  the Dollar  equivalent as of
such date of original  issuance of the amount  determined  as provided in clause
(i) above) of such Security,  (iii) the principal amount of any Indexed Security
that may be counted in making such  determination  or calculation and that shall
be deemed  outstanding  for such purpose  shall be equal to the  principal  face
amount of such Indexed Security at original issuance,  unless otherwise provided
with respect to such Security pursuant to Section 301, and (iv) Securities owned
by the Company or any other obligor upon the  Securities or any Affiliate of the
Company  or of such  other  obligor  shall be  disregarded  and deemed not to be
Outstanding,  except that, in determining whether the Trustee shall be protected
in  making  such  calculation  or in  relying  upon  any such  request,  

                                       -5-





demand,
authorization,  direction,  notice, consent or waiver, only Securities which the
Trustee knows to be so owned shall be so disregarded.  Securities so owned which
have been  pledged in good faith may be regarded as  Outstanding  if the pledgee
establishes  to the  satisfaction  of the Trustee the pledgee's  right so to act
with respect to such  Securities  and that the pledgee is not the Company or any
other  obligor upon the  Securities  or any  Affiliate of the Company or of such
other obligor.

                 "Paying  Agent" means any Person  authorized  by the Company to
pay the  principal of (and  premium,  if any) or interest on any  Securities  or
coupons on behalf of the Company.

                 "Person" means any individual, corporation,  partnership, joint
venture,  association,  joint-stock  company,  trust, limited liability company,
unincorporated organization or government or any agency or political subdivision
thereof.

                 "Place of Payment", when used with respect to the Securities of
or within any  series,  means the place or places  where the  principal  of (and
premium,  if any) and  interest on such  Securities  are payable as specified as
contemplated by Sections 301 and 1002.

                 "Predecessor  Security" of any particular  Security means every
previous Security evidencing all or a portion of the same debt as that evidenced
by such  particular  Security;  and,  for the purposes of this  definition,  any
Security  authenticated  and  delivered  under Section 306 in exchange for or in
lieu of a mutilated, destroyed, lost or stolen Security or a Security to which a
mutilated,  destroyed,  lost or  stolen  coupon  appertains  shall be  deemed to
evidence the same debt as the mutilated,  destroyed,  lost or stolen Security or
the  Security  to  which  the  mutilated,   destroyed,  lost  or  stolen  coupon
appertains.

                 "Redemption Date", when used with respect to any Security to be
redeemed,  in whole or in part,  means the date fixed for such  redemption by or
pursuant to this Indenture.

                 "Redemption  Price",  when used with respect to any Security to
be  redeemed,  means the price at which it is to be  redeemed  pursuant  to this
Indenture.

                 "Registered  Security"  shall  mean  any  Security  established
pursuant to Section 201 which is registered in the Security Register.

                 "Regular Record Date" for the interest  payable on any Interest
Payment Date on the Registered Securities of or within any series means the date
specified  for that purpose as  contemplated  by Section  301,  whether or not a
Business Day.

                 "Repayment Date" means,  when used with respect to any Security
to be repaid at the option of the Holder,  the date fixed for such  repayment by
or pursuant to this Indenture.

                 "Responsible  Officer",  when used with respect to the Trustee,
means the chairman or vice-chairman  of the board of directors,  the chairman or
vice-chairman  of  the  executive  committee  of the  board  of  directors,  the
president,  any vice president  (whether or not designated by a number or a word
or words added before or after the title "vice president"),  the secretary,  any
assistant secretary,  the treasurer,  any assistant treasurer,  the cashier, any
assistant cashier, any trust officer, the controller or any other officer of the
Trustee  customarily  performing  functions similar to those performed by any of
the above  designated  officers  and also  means with  respect  to a  particular
corporate  trust  matter,  any other  officer  to whom such  matter is  referred
because of such officer's knowledge and familiarity with the particular subject.

                 "Security"  has the meaning stated in the first recital of this
Indenture and, more particularly, means any Security or Securities authenticated
and delivered  under this  Indenture;  provided,  however,  that, if at any time
there  is  more  than  one  Person  acting  as  Trustee  under  this  Indenture,
"Securities"  with  respect to the  Indenture as to which such 

                                       -6-





Person is Trustee
shall have the meaning  stated in the first recital of this  Indenture and shall
more  particularly  mean  Securities  authenticated  and  delivered  under  this
Indenture,  exclusive,  however,  of  Securities  of any series as to which such
Person is not Trustee.

                 "Security   Register"   and  "Security   Registrar"   have  the
respective meanings specified in Section 305.

                 "Significant  Subsidiary"  means  any  Subsidiary  which  is  a
"significant  subsidiary" (as defined in Article I, Rule 1-02 of Regulation S-X,
promulgated under the Securities Act of 1933, as amended) of the Company.

                 "Special Record Date" for the payment of any Defaulted Interest
on the  Registered  Securities of or within any series means a date fixed by the
Trustee pursuant to Section 307.

                 "Stated  Maturity",  when used with  respect to any Security or
any  installment  of  principal  thereof  or  interest  thereon,  means the date
specified in such Security or a coupon representing such installment of interest
as the fixed date on which the principal of such Security or such installment of
principal or interest is due and payable.

                 "Subsidiary"  means a corporation a majority of the outstanding
voting stock of which is owned, directly or indirectly, by the Company or by one
or more other Subsidiaries of the Company.  For the purposes of this definition,
"voting  stock" means stock having  voting power for the election of  directors,
whether at all times or only so long as no senior class of stock has such voting
power by reason of any contingency.

                 "Trust Indenture Act" or "TIA" means the Trust Indenture Act of
1939,  as  amended  and as in force at the date as of which this  Indenture  was
executed, except as provided in Section 905.

                 "Trustee"  means the Person named as the "Trustee" in the first
paragraph of this  Indenture  until a successor  Trustee  shall have become such
pursuant  to  the  applicable  provisions  of  this  Indenture,  and  thereafter
"Trustee"  shall mean or include  each  Person who is then a Trustee  hereunder;
provided,  however,  that if at any  time  there is more  than one such  Person,
"Trustee" as used with respect to the  Securities  of any series shall mean only
the Trustee with respect to Securities of that series.

                 "United States" means,  unless otherwise specified with respect
to any  Securities  pursuant  to  Section  301,  the  United  States of  America
(including  the states and the  District  of  Columbia),  its  territories,  its
possessions and other areas subject to its jurisdiction.

                 "United States person" means,  unless otherwise  specified with
respect to any  Securities  pursuant  to Section  301,  an  individual  who is a
citizen or resident of the United States,  a  corporation,  partnership or other
entity created  organized in or under the laws of the United States or an estate
or trust the income of which is subject to United States federal income taxation
regardless of its source.

                 "Yield to Maturity"  means the yield to  maturity,  computed at
the time of  issuance  of a Security  (or,  if  applicable,  at the most  recent
redetermination  of interest on such Security) and as set forth in such Security
in accordance  with  generally  accepted  United  States bond yield  computation
principles.

                 SECTION 102.  Compliance  Certificates  and Opinions.  Upon any
application  or request by the Company to the  Trustee to take any action  under
any  provision of this  Indenture,  the Company  shall furnish to the Trustee an
Officers'  Certificate stating that all conditions  precedent,  if any, provided
for in this  Indenture  relating to the proposed  action have been complied with
and an Opinion of Counsel  stating  that in the opinion of such counsel all such
conditions  precedent,  if any, have been complied with, except that in the case
of any such  application or request as to which the furnishing of such documents
is  specifically  required by any provision of this  Indenture  relating to such
particular  application or request, no additional certificate or opinion need be
furnished.


                                       -7-





                 Every  certificate or opinion with respect to compliance with a
condition or covenant  provided for in this  Indenture  (including  certificates
delivered pursuant to Section 1006) shall include:

                           (1) a statement  that each  individual  signing  such
         certificate  or opinion has read such  condition  or  covenant  and the
         definitions herein relating thereto;

                           (2) a brief  statement  as to the nature and scope of
         the examination or investigation  upon which the statements or opinions
         contained in such certificate or opinion are based;

                           (3) a  statement  that,  in the  opinion of each such
         individual,  he  has  made  such  examination  or  investigation  as is
         necessary to enable him to express an informed opinion as to whether or
         not such condition or covenant has been complied with; and

                           (4) a statement as to whether, in the opinion of each
         such individual, such condition or covenant has been complied with.

                 SECTION  103.  Form of Documents  Delivered to Trustee.  In any
case where  several  matters are  required to be  certified  by or covered by an
opinion of any specified  Person,  it is not necessary  that all such matters be
certified  by, or covered by the opinion of, only one such Person,  or that they
be so certified or covered by only one document, but one such Person may certify
or give an opinion as to some  matters and one or more other such  Persons as to
other  matters,  and any such  Person may  certify or give an opinion as to such
matters in one or several documents.

                 Any  certificate or opinion of an officer of the Company may be
based, insofar as it relates to legal matters,  upon an Opinion of Counsel, or a
certificate of or representations  by counsel,  unless such officer knows, or in
the exercise of reasonable  care should know,  that the opinion,  certificate or
representations  with  respect  to the  matters  upon which his  certificate  or
opinion is based are  erroneous.  Any such  Opinion of Counsel,  certificate  or
representations may be based,  insofar as it relates to factual matters,  upon a
certificate or opinion of, or representations  by, an officer or officers of the
Company  or any  Subsidiary  stating  that the  information  as to such  factual
matters is in the  possession  of the  Company or such  Subsidiary,  unless such
counsel  knows that the  certificate  or opinion or  representations  as to such
matters are erroneous.

                 Where any Person is  required  to make,  give or execute two or
more applications,  requests, consents,  certificates,  statements,  opinions or
other instruments under this Indenture,  they may, but need not, be consolidated
and form one instrument.

                 SECTION 104.  Acts of Holders.

                 (a) Any  request,  demand,  authorization,  direction,  notice,
consent,  waiver or other action provided by this Indenture to be given or taken
by Holders of the Outstanding Securities of all series or one or more series, as
the case may be, may be embodied in and evidenced by one or more  instruments of
substantially  similar  tenor signed by such Holders in person or by agents duly
appointed  in  writing.  If  Securities  of a  series  are  issuable  as  Bearer
Securities,  any request,  demand,  authorization,  direction,  notice, consent,
waiver  or  other  action  provided  by this  Indenture  to be given or taken by
Holders of  Securities  of such  series may,  alternatively,  be embodied in and
evidenced by the record of Holders of  Securities of such series voting in favor
thereof,  either in person or by  proxies  duly  appointed  in  writing,  at any
meeting  of  Holders  of  Securities  of such  series  duly  called  and held in
accordance  with the  provisions of Article  Fifteen,  or a combination  of such
instruments and any such record.  Except as herein otherwise expressly provided,
such action shall become effective when such instrument or instruments or record
or both are delivered to the Trustee and, where it is hereby expressly required,
to the Company.  Such  instrument  or  instruments  and any such record (and the
action embodied therein and evidenced  thereby) are herein sometimes referred to
as the "Act" of the Holders  signing such instrument or instruments or so voting
at any such meeting.  Proof of execution of any such  instrument or of a writing
appointing any such agent, or of the holding by any Person of a Security,  shall
be sufficient  for any purpose of this  Indenture and conclusive in favor of the
Trustee and the Company and any agent of 

                                       -8-





the Trustee or the Company, if made in the manner provided in this Section.  The
record of any  meeting of Holders  of  Securities  shall be proved in the manner
provided in Section 1506.

                 (b) The fact and date of the  execution  by any  Person  of any
such  instrument  or writing may be proved by the affidavit of a witness of such
execution or by a certificate of a notary public or other officer  authorized by
law to take  acknowledgments  of deeds,  certifying that the individual  signing
such instrument or writing acknowledged to him the execution thereof. Where such
execution  is by a  signer  acting  in a  capacity  other  than  his  individual
capacity,  such certificate or affidavit shall also constitute  sufficient proof
of his authority.  The fact and date of the execution of any such  instrument or
writing,  or the authority of the Person  executing the same, may also be proved
in any other reasonable manner which the Trustee deems sufficient.

                 (c) The ownership of Registered  Securities  shall be proved by
the Security Register.

                 (d) The  ownership  of Bearer  Securities  may be proved by the
production  of  such  Bearer  Securities  or  by  a  certificate   executed,  as
depositary,  by any trust company,  bank, banker or other  depositary,  wherever
situated, if such certificate shall be deemed by the Trustee to be satisfactory,
showing that at the date therein  mentioned such Person had on deposit with such
depositary, or exhibited to it, the Bearer Securities therein described; or such
facts may be proved by the  certificate  or affidavit of the Person holding such
Bearer Securities,  if such certificate or affidavit is deemed by the Trustee to
be  satisfactory.  The Trustee and the Company may assume that such ownership of
any Bearer Security continues until (1) another certificate or affidavit bearing
a later date issued in respect of the same Bearer  Security is produced,  or (2)
such Bearer  Security is  produced to the Trustee by some other  Person,  or (3)
such Bearer  Security is surrendered in exchange for a Registered  Security,  or
(4) such  Bearer  Security is no longer  Outstanding.  The  ownership  of Bearer
Securities  may also be proved  in any other  manner  which  the  Trustee  deems
sufficient.

                 (e) If the Company shall solicit from the Holders of Registered
Securities  any request,  demand,  authorization,  direction,  notice,  consent,
waiver or other Act, the Company  may, at its option,  in or pursuant to a Board
Resolution,  fix in  advance  a record  date for the  determination  of  Holders
entitled  to  give  such  request,  demand,  authorization,  direction,  notice,
consent, waiver or other Act, but the Company shall have no obligation to do so.
Notwithstanding  TIA Section  316(c),  such record date shall be the record date
specified  in or  pursuant to such Board  Resolution,  which shall be a date not
earlier  than  the date 30 days  prior  to the  first  solicitation  of  Holders
generally in connection  therewith and not later than the date such solicitation
is  completed.   If  such  a  record  date  is  fixed,  such  request,   demand,
authorization,  direction,  notice,  consent,  waiver  or other Act may be given
before or after such record date, but only the Holders of record at the close of
business on such  record date shall be deemed to be Holders for the  purposes of
determining   whether  Holders  of  the  requisite   proportion  of  Outstanding
Securities  have  authorized  or agreed or  consented to such  request,  demand,
authorization,  direction,  notice,  consent,  waiver or other Act, and for that
purpose the  Outstanding  Securities  shall be computed as of such record  date;
provided that no such authorization, agreement or consent by the Holders on such
record date shall be deemed effective unless it shall become effective  pursuant
to the  provisions  of this  Indenture  not later than eleven  months  after the
record date.

                 (f) Any  request,  demand,  authorization,  direction,  notice,
consent,  waiver or other Act of the  Holder of any  Security  shall  bind every
future Holder of the same Security and the Holder of every Security  issued upon
the registration of transfer thereof or in exchange  therefor or in lieu thereof
in respect of anything done, omitted or suffered to be done by the Trustee,  any
Security Registrar, any Paying Agent, any Authenticating Agent or the Company in
reliance  thereon,  whether  or not  notation  of such  action is made upon such
Security.

                 SECTION  105.  Notices,  etc.,  to  Trustee  and  Company.  Any
request,  demand,  authorization,  direction,  notice, consent, waiver or Act of
Holders or other  document  provided or permitted  by this  Indenture to be made
upon, given or furnished to, or filed with,


                                       -9-





                           (1) the Trustee by any Holder or by the Company shall
         be sufficient for every purpose hereunder if made, given,  furnished or
         filed in writing to or with the Trustee at its Corporate  Trust Office,
         Attention: ______________________, or

                           (2) the Company by the Trustee or by any Holder shall
         be sufficient  for every purpose  hereunder  (unless  otherwise  herein
         expressly  provided)  if in writing  and mailed,  first  class  postage
         prepaid, to the Company addressed to it at the address of its principal
         office  specified in the first  paragraph  of this  Indenture or at any
         other  address  previously  furnished  in writing to the Trustee by the
         Company.

                 SECTION 106.  Notice to Holders;  Waiver.  Where this Indenture
provides  for  notice of any event to Holders of  Registered  Securities  by the
Company  or the  Trustee,  such  notice  shall  be  sufficiently  given  (unless
otherwise  herein  expressly  provided)  if in writing and  mailed,  first-class
postage  prepaid,  to each such Holder affected by such event, at his address as
it appears in the Security  Register,  not later than the latest  date,  and not
earlier than the earliest date, prescribed for the giving of such notice. In any
case where notice to Holders of Registered  Securities is given by mail, neither
the failure to mail such notice,  nor any defect in any notice so mailed, to any
particular  Holder shall affect the  sufficiency  of such notice with respect to
other  Holders of  Registered  Securities  or the  sufficiency  of any notice to
Holders of Bearer  Securities given as provided  herein.  Any notice mailed to a
Registered Holder in the manner herein  prescribed shall be conclusively  deemed
to have been  received  by such  Holder,  whether  or not such  Holder  actually
receives such notice.

                 If by reason of the suspension of or  irregularities in regular
mail service or by reason of any other cause it shall be  impracticable  to give
such notice by mail, then such notification to Holders of Registered  Securities
as shall be made with the approval of the Trustee shall  constitute a sufficient
notification to such Holders for every purpose hereunder.

                 Except as  otherwise  expressly  provided  herein or  otherwise
specified  with respect to any  Securities  pursuant to Section 301,  where this
Indenture provides for notice to Holders of Bearer Securities of any event, such
notice shall be  sufficiently  given if published in an Authorized  Newspaper in
The City of New York and in such  other  city or cities as may be  specified  in
such  Securities on a Business Day,  such  publication  to be not later than the
latest date, and not earlier than the earliest  date,  prescribed for the giving
of such  notice.  Any such notice shall be deemed to have been given on the date
of such  publication  or, if published  more than once, on the date of the first
such publication.

                 If by reason of the suspension of publication of any Authorized
Newspaper or  Authorized  Newspapers or by reason of any other cause it shall be
impracticable to publish any notice to Holders of Bearer  Securities as provided
above,  then such notification to Holders of Bearer Securities as shall be given
with the  approval of the Trustee  shall  constitute  sufficient  notice to such
Holders  for every  purpose  hereunder.  Neither  the  failure to give notice by
publication to any particular Holder of Bearer Securities as provided above, nor
any defect in any notice so  published,  shall  affect the  sufficiency  of such
notice with respect to other Holders of Bearer  Securities or the sufficiency of
any notice to Holders of Registered Securities given as provided herein.

                 Any request, demand, authorization,  direction, notice, consent
or waiver  required or permitted  under this  Indenture  shall be in the English
language, except that any published notice may be in an official language of the
country of publication.

                 Where this  Indenture  provides for notice in any manner,  such
notice may be waived in writing by the Person  entitled to receive  such notice,
either  before or after the event,  and such waiver shall be the  equivalent  of
such notice.  Waivers of notice by Holders shall be filed with the Trustee,  but
such filing  shall not be a condition  precedent  to the  validity of any action
taken in reliance upon such waiver.

                 SECTION  107.  Effect of Headings  and Table of  Contents.  The
Article  and  Section  headings  herein  and  the  Table  of  Contents  are  for
convenience only and shall not affect the construction hereof.

                                      -10-





                 SECTION  108.   Successors  and  Assigns.   All  covenants  and
agreements  in this  Indenture  by the  Company  shall bind its  successors  and
assigns, whether so expressed or not.

                 SECTION 109. Separability Clause. In case any provision in this
Indenture  or  in  any   Security  or  coupon  shall  be  invalid,   illegal  or
unenforceable,  the  validity,  legality  and  enforceability  of the  remaining
provisions shall not in any way be affected or impaired thereby.

                 SECTION 110.  Benefits of Indenture.  Nothing in this Indenture
or in the Securities or coupons,  express or implied,  shall give to any Person,
other than the parties hereto,  any Security  Registrar,  any Paying Agent,  any
Authenticating  Agent and their successors hereunder and the Holders any benefit
or any legal or equitable right, remedy or claim under this Indenture.

                 SECTION 111.  Governing  Law. This Indenture and the Securities
and coupons shall be governed by and construed in accordance with the law of The
Commonwealth  of  Massachusetts.  This Indenture is subject to the provisions of
the TIA that are required to be part of this Indenture and shall,  to the extent
applicable, be governed by such provisions.

                 SECTION  112.  Legal  Holidays.  In any case where any Interest
Payment Date, Redemption Date, Repayment Date, sinking fund payment date, Stated
Maturity or Maturity of any Security shall not be a Business Day at any Place of
Payment,  then  (notwithstanding  any other  provision of this  Indenture or any
Security or coupon other than a provision in the  Securities of any series which
specifically states that such provision shall apply in lieu hereof),  payment of
interest or any Additional Amounts or principal (and premium, if any) or sinking
fund payment need not be made at such Place of Payment on such date,  but may be
made on the next succeeding  Business Day at such Place of Payment with the same
force and  effect as if made on the  Interest  Payment  Date,  Redemption  Date,
Repayment  Date or sinking  fund  payment  date,  or at the Stated  Maturity  or
Maturity;  provided  that no interest  shall accrue on the amount so payable for
the period from and after such Interest Payment Date, Redemption Date, Repayment
Date,  sinking fund payment date,  Stated Maturity or Maturity,  as the case may
be.


                                   ARTICLE TWO

                                SECURITIES FORMS

                 SECTION 201. Forms of Securities. The Registered Securities, if
any,  of each  series  and the Bearer  Securities,  if any,  of each  series and
related coupons shall be in  substantially  the forms as shall be established in
one or more indentures  supplemental  hereto or approved from time to time by or
pursuant to a Board  Resolution in accordance  with Section 301, shall have such
appropriate  insertions,  omissions,  substitutions  and other variations as are
required or permitted by this  Indenture or any indenture  supplemental  hereto,
and may  have  such  letters,  numbers  or  other  marks  of  identification  or
designation and such legends or  endorsements  placed thereon as the Company may
deem  appropriate  and as are  not  inconsistent  with  the  provisions  of this
Indenture,  or as may be  required  to  comply  with any law or with any rule or
regulation  made  pursuant  thereto  or  with  any  rule  or  regulation  of any
securities  exchange  on which the  Securities  may be listed,  or to conform to
usage.

                 Unless  otherwise  specified  as  contemplated  by Section 301,
Bearer Securities shall have interest coupons attached.

                 The  definitive   Securities  and  coupons  shall  be  printed,
lithographed  or engraved or produced by any  combination  of these methods on a
steel engraved border or steel engraved  borders or may be produced in any other
manner,  all  as  determined  by the  officers  of the  Company  executing  such
Securities  or coupons,  as evidenced by their  execution of such  Securities or
coupons.


                                      -11-





                 SECTION 202. Form of Trustee's  Certificate of  Authentication.
Subject to Section 611, the Trustee's  certificate of authentication shall be in
substantially the following form:

         This is one of the Securities of the series designated therein referred
to in the within-mentioned Indenture.

                           ________________________________
                                                 as Trustee


                           By______________________________
                                         Authorized Officer

                 SECTION 203.  Securities Issuable in Global Form. If Securities
of or within a series  are  issuable  in global  form,  as  specified  in and as
contemplated by Section 301, then, notwithstanding clause (8) of Section 301 and
the  provisions of Section 302, any such Security  shall  represent  such of the
Outstanding  Securities  of such  series as shall be  specified  therein and may
provide that it shall represent the aggregate  amount of Outstanding  Securities
of such series from time to time endorsed  thereon and that the aggregate amount
of Outstanding  Securities of such series  represented  thereby may from time to
time be  increased  or  decreased to reflect  exchanges.  Any  endorsement  of a
Security in global form to reflect  the amount,  or any  increase or decrease in
the amount, of Outstanding  Securities  represented thereby shall be made by the
Trustee in such manner and upon instructions  given by such Person or Persons as
shall be  specified  therein  or in the  Company  Order to be  delivered  to the
Trustee pursuant to Section 303 or 304. Subject to the provisions of Section 303
and, if  applicable,  Section 304, the Trustee  shall  deliver and redeliver any
Security in permanent global form in the manner and upon  instructions  given by
the Person or Persons specified therein or in the applicable Company Order. If a
Company  Order  pursuant to Section 303 or 304 has been, or  simultaneously  is,
delivered,  any  instructions  by the Company  with  respect to  endorsement  or
delivery or redelivery of a Security in global form shall be in writing but need
not  comply  with  Section  102 and need not be  accompanied  by an  Opinion  of
Counsel.

                 The  provisions of the last sentence of Section 303 shall apply
to any Security  represented  by a Security in global form if such  Security was
never issued and sold by the Company and the Company delivers to the Trustee the
Security in global  form  together  with  written  instructions  (which need not
comply with  Section 102 and need not be  accompanied  by an Opinion of Counsel)
with regard to the reduction in the principal  amount of Securities  represented
thereby,  together with the written statement  contemplated by the last sentence
of Section 303.

                 Notwithstanding the provisions of Section 307, unless otherwise
specified  as  contemplated  by Section  301,  payment of  principal  of and any
premium and interest on any  Security in permanent  global form shall be made to
the Person or Persons specified therein.

                 Notwithstanding  the  provisions  of Section  308 and except as
provided in the preceding  paragraph,  the Company, the Trustee and any agent of
the Company and the Trustee shall treat as the Holder of such  principal  amount
of Outstanding  Securities represented by a permanent global Security (i) in the
case of a permanent  global  Security  in  registered  form,  the Holder of such
permanent  global Security in registered form or (ii) in the case of a permanent
global Security in bearer form, Euroclear or CEDEL.


                                  ARTICLE THREE

                                 THE SECURITIES

                 SECTION  301.  Amount  Unlimited;   Issuable  in  Series.   The
aggregate  principal  amount  of  Securities  which  may  be  authenticated  and
delivered under this Indenture is unlimited.


                                      -12-


                 The Securities may be issued in one or more series. There shall
be established in one or more Board Resolutions or pursuant to authority granted
by one or more Board  Resolutions  and,  subject to Section 303,  set forth,  or
determined in the manner provided, in an Officers'  Certificate,  or established
in one or  more  indentures  supplemental  hereto,  prior  to  the  issuance  of
Securities of any series,  any or all of the following,  as applicable  (each of
which (except for the matters set forth in clauses (1), (2) and (14) below),  if
so provided,  may be determined from time to time by the Company with respect to
unissued Securities of the series when issued from time to time):

                           (1) the title of the  Securities of the series (which
         shall  distinguish  the Securities of such series from all other series
         of Securities);

                           (2) any limit upon the aggregate  principal amount of
         the  Securities of the series that may be  authenticated  and delivered
         under this Indenture (except for Securities authenticated and delivered
         upon  registration  of transfer of, or in exchange  for, or in lieu of,
         other  Securities of the series pursuant to Section 304, 305, 306, 906,
         1107 or 1305);

                           (3) the date or dates,  or the  method by which  such
         date or  dates  will be  determined,  on  which  the  principal  of the
         Securities of the series shall be payable;

                           (4) the rate or rates at which the  Securities of the
         series shall bear interest, if any, or the method by which such rate or
         rates shall be  determined,  the date or dates from which such interest
         shall  accrue  or the  method  by which  such  date or  dates  shall be
         determined,  the Interest  Payment Dates on which such interest will be
         payable and the Regular  Record Date, if any, for the interest  payable
         on any Registered  Security on any Interest Payment Date, or the method
         by which  such  date  shall be  determined,  and the basis  upon  which
         interest  shall be  calculated  if other than that of a 360-day year of
         twelve 30-day months;

                           (5) the place or places where the  principal  of, any
         premium and interest on and any Additional  Amounts  payable in respect
         of,  Securities  of  the  series  shall  be  payable,   any  Registered
         Securities  of  the  series  may be  surrendered  for  registration  of
         transfer,  exchange or conversion and notices or demands to or upon the
         Company in respect of the  Securities of the series and this  Indenture
         may be served;

                           (6) the period or periods within which or the date or
         dates on which,  the price or  prices  at  which,  and other  terms and
         conditions  upon which  Securities  of the series may be  redeemed,  in
         whole or in part,  at the option of the  Company,  if the Company is to
         have the option;

                           (7) the obligation, if any, of the Company to redeem,
         repay or purchase Securities of the series pursuant to any sinking fund
         or analogous  provision or at the option of a Holder  thereof,  and the
         period or periods within which or the date or dates on which, the price
         or  prices  at  which,  and  other  terms  and  conditions  upon  which
         Securities  of the series shall be redeemed,  repaid or  purchased,  in
         whole or in part, pursuant to such obligation;

                           (8) if other  than  denominations  of $1,000  and any
         integral  multiple  thereof,  the denominations in which any Registered
         Securities  of the series  shall be issuable  and the  denomination  or
         denominations  in which any Bearer  Securities  of the series  shall be
         issuable;

                           (9) if other than  Dollars,  the Foreign  Currency or
         Currencies in which payment of the principal of (and premium,  if any),
         interest, if any, on, and Additional Amounts, if any, on the Securities
         of the series shall be payable,  in which the  Securities of the series
         shall be redeemed or purchased or in which the Securities of the series
         shall be denominated;

                           (10) if other than the principal amount thereof,  the
         portion of the principal  amount of Securities of the series that shall
         be payable upon  declaration of  acceleration  of the Maturity  thereof
         pursuant 

                                      -13-

         to Section 502 or, if applicable,  the portion of the principal  amount
         of Securities of the series that is convertible in accordance  with the
         provisions of this Indenture, or the method by which such portion shall
         be determined;

                           (11)  whether the amount of payments of  principal of
         (and  premium,  if any) or interest,  if any, on the  Securities of the
         series may be determined  with reference to an index,  formula or other
         method  (which  index,   formula  or  method  may  be  based,   without
         limitation,  on one  or  more  currencies,  currency  units,  composite
         currencies,  commodities,  equity  indices or other  indices),  and the
         manner in which such amounts shall be determined;

                           (12) whether the principal of (and  premium,  if any)
         or interest, if any on or Additional Amounts, if any, on the Securities
         of the series are to be  payable,  at the  election of the Company or a
         Holder thereof, in a currency or currencies,  currency unit or units or
         composite  currency  or  currencies  other  than  that  in  which  such
         Securities  are  denominated  or stated to be  payable,  the  period or
         periods  within which,  and the terms and conditions  upon which,  such
         election  may be made,  and the time and manner of, and identity of the
         exchange rate agent with  responsibility  for  determining the exchange
         rate  between the  currency or  currencies,  currency  unit or units or
         composite   currency  or  currencies  in  which  such   Securities  are
         denominated  or stated to be payable and the  currency  or  currencies,
         currency  unit or units or composite  currency or  currencies  in which
         such Securities are to be paid;

                           (13) provisions,  if any,  granting special rights to
         the Holders of  Securities  of the series upon the  occurrence  of such
         events as may be specified;

                           (14)  any  deletions   from,   modifications   of  or
         additions  to the Events of Default or  covenants  of the  Company  set
         forth in this  Indenture  with  respect  to  Securities  of the  series
         (whether or not such Events of Default or covenants are consistent with
         the Events of Default or covenants set forth herein);

                           (15)  whether  Securities  of  the  series  are to be
         issuable as Registered  Securities,  Bearer Securities (with or without
         coupons) or both,  any  restrictions  applicable to the offer,  sale or
         delivery  of  Bearer   Securities  and  the  terms  upon  which  Bearer
         Securities of the series may be exchanged for Registered  Securities of
         the  series  and  vice  versa  (if  permitted  by  applicable  laws and
         regulations),  whether any  Securities of the series are to be issuable
         initially in temporary  global form and whether any  Securities  of the
         series are to be  issuable  in  permanent  global  form with or without
         coupons and, if so, whether  beneficial owners of interests in any such
         permanent global Security may exchange such interests for Securities of
         such series and of like tenor of any authorized  form and  denomination
         and the  circumstances  under which any such  exchanges  may occur,  if
         other than in the manner  provided in Section 305,  and, if  Registered
         Securities of the series are to be issuable as a global  Security,  the
         identity of the depositary for such series;

                           (16) the date as of which any  Bearer  Securities  of
         the series and any temporary global Security  representing  Outstanding
         Securities  of the  series  shall be  dated  if other  than the date of
         original issuance of the first Security of the series to be issued;

                           (17)  the  Person  to  whom  any   interest   on  any
         Registered  Security of the series shall be payable,  if other than the
         Person  in  whose  name  that  Security  (or  one or  more  Predecessor
         Securities)  is  registered  at the close of  business  on the  Regular
         Record Date for such  interest,  the manner in which,  or the Person to
         whom,  any  interest  on any Bearer  Security  of the  series  shall be
         payable,  if  otherwise  than upon  presentation  and  surrender of the
         coupons  appertaining  thereto as they severally mature, and the extent
         to which, or the manner in which,  any interest  payable on a temporary
         global Security on an Interest  Payment Date will be paid if other than
         in the manner provided in Section 304;

                           (18) the  applicability,  if any,  of  Sections  1402
         and/or  1403 to the  Securities  of the  series and any  provisions  in
         modification  of, in addition to or in lieu of any of the provisions of
         Article Fourteen;

                                      -14-

                           (19)  if the  Securities  of  such  series  are to be
         issuable  in  definitive  form  (whether  upon  original  issue or upon
         exchange of a temporary  Security of such  series) only upon receipt of
         certain  certificates  or  other  documents  or  satisfaction  of other
         conditions, then the form and/or terms of such certificates,  documents
         or conditions;

                           (20) if the Securities of the series are to be issued
         upon the  exercise  of  warrants,  the time,  manner and place for such
         Securities to be authenticated and delivered;

                           (21) whether and under what circumstances the Company
         will pay  Additional  Amounts as  contemplated  by Section  1007 on the
         Securities  of the  series  to any  Holder  who is not a United  States
         person  (including any  modification to the definition of such term) in
         respect of any tax,  assessment  or  governmental  charge  and,  if so,
         whether  the  Company  will have the option to redeem  such  Securities
         rather  than pay such  Additional  Amounts  (and the  terms of any such
         option);

                           (22) the obligation, if any, of the Company to permit
         the  conversion of the  Securities of such series into Common Shares or
         Preferred  Shares of the Company or other  securities,  as the case may
         be, and the terms and conditions  upon which such  conversion  shall be
         effected (including,  without limitation,  the initial conversion price
         or rate,  the  conversion  period,  any  adjustment  of the  applicable
         conversion  price and any  requirements  relative to the reservation of
         such shares for purposes of conversion);

                           (23) the terms and  conditions,  if any,  upon  which
         payment of the Securities of such series shall be  subordinated  to the
         Securities  of  another  series or other  indebtedness  of the  Company
         (including, without limitation, indebtedness which ranks senior to such
         Securities;  restrictions  on  payments  to Holders of such  Securities
         while a default with respect to such senior indebtedness is continuing;
         restrictions,  if any, on  payments  to the Holders of such  Securities
         following an Event of Default; and any requirements for Holders of such
         Securities  to remit  certain  payments  to the  holders of such senior
         indebtedness);

                           (24)  if  the  Securities  of  the  series  are to be
         guaranteed, the term and conditions of such guarantee;

                           (25)  if  the  Securities  of  the  series  are to be
         secured,  the terms and  conditions  pertaining  to the  security and a
         description of the collateral pledged as security ;

                           (26) if other than the Trustee,  the identity of each
         Security Registrar and/or Paying Agent for the series; and

                           (27) any other terms of the series (which terms shall
         not be inconsistent with the provisions of this Indenture).

                 All  Securities of any one series and the coupons  appertaining
to any Bearer Securities of such series shall be substantially identical except,
in the case of  Registered  Securities,  as to  denominations  and except as may
otherwise be provided in or pursuant to the Board  Resolution  establishing  the
series (subject to Section 303) and set forth in an Officers'  Certificate or in
any indenture  supplemental hereto. All Securities of any one series need not be
issued  at the same  time  and,  unless  otherwise  provided,  a  series  may be
reopened,  without the  consent of the  Holders,  for  issuances  of  additional
Securities of such series.

                 If  any of  the  terms  of the  Securities  of any  series  are
established by action taken pursuant to one or more Board Resolutions, a copy of
an appropriate  record of such action(s)  shall be certified by the Secretary or
an Assistant  Secretary of the Company and  delivered to the Trustee at or prior
to the  delivery of the  Officers'  Certificate  setting  forth the terms of the
Securities of such series.

                                      -15-

                 SECTION 302. Denominations. The Securities of each series shall
be issuable in such  denominations  as shall be  specified  as  contemplated  by
Section 301. With respect to Securities of any series denominated in Dollars, in
the absence of any such  provisions,  the Registered  Securities of such series,
other than  Registered  Securities  issued in global  form  (which may be of any
denomination),  shall be issuable in  denominations  of $1,000 and any  integral
multiple thereof.

                 SECTION 303.  Execution,  Authentication,  Delivery and Dating.
The Securities and any coupons  appertaining thereto shall be executed on behalf
of the  Company  by its  Chairman  of the  Board and  Chief  Executive  Officer,
President or one of its Vice Presidents,  under its seal reproduced thereon, and
attested by its Secretary or one of its Assistant Secretaries.  The signature of
any of these  officers on the  Securities and coupons may be manual or facsimile
signatures  of the  present or any future  such  authorized  officer  and may be
imprinted or otherwise reproduced on the Securities.

                 Securities   or  coupons   bearing  the  manual  or   facsimile
signatures  of  individuals  who  were at any time the  proper  officers  of the
Company shall bind the Company,  notwithstanding that such individuals or any of
them have ceased to hold such offices prior to the  authentication  and delivery
of such  Securities or did not hold such offices at the date of such  Securities
or coupons.

                 At any time and  from  time to time  after  the  execution  and
delivery of this  Indenture,  the Company may deliver  Securities of any series,
together with any coupon  appertaining  thereto,  executed by the Company to the
Trustee for authentication, together with a Company Order for the authentication
and delivery of such Securities,  and the Trustee in accordance with the Company
Order shall authenticate and deliver such Securities;  provided,  however, that,
in connection with its original issuance,  no Bearer Security shall be mailed or
otherwise  delivered to any location in the United States;  and provided further
that,  unless  otherwise  specified  with  respect to any  series of  Securities
pursuant to Section 301, a Bearer  Security may be delivered in connection  with
its  original  issuance  only if the  Person  entitled  to receive  such  Bearer
Security shall have furnished a certificate in the form set forth in Exhibit A-1
to this Indenture or such other  certificate as may be specified with respect to
any series of Securities  pursuant to Section 301, dated no earlier than 15 days
prior to the earlier of the date on which such Bearer  Security is delivered and
the date on which any temporary  Security  first becomes  exchangeable  for such
Bearer Security in accordance with the terms of such temporary Security and this
Indenture.  If any Security shall be  represented  by a permanent  global Bearer
Security,  then, for purposes of this Section and Section 304, the notation of a
beneficial  owner's interest therein upon original  issuance of such Security or
upon exchange of a portion of a temporary  global Security shall be deemed to be
delivery in connection  with its original  issuance of such  beneficial  owner's
interest in such permanent global Security.  Except as permitted by Section 306,
the Trustee shall not  authenticate  and deliver any Bearer  Security unless all
appurtenant  coupons for interest then matured have been detached and cancelled.
If all the  Securities of any series are not to be issued at one time and if the
Board  Resolution or supplemental  indenture  establishing  such series shall so
permit,  such Company Order may set forth  procedures  acceptable to the Trustee
for the issuance of such  Securities  and  determining  the terms of  particular
Securities of such series, such as interest rate or formula, maturity date, date
of issuance and date from which interest shall accrue.  In  authenticating  such
Securities,  and accepting the additional  responsibilities under this Indenture
in relation to such  Securities,  the Trustee shall be entitled to receive,  and
(subject to TIA Sections  315(a)  through  315(d))  shall be fully  protected in
relying upon,

                           (i)      an Opinion of Counsel stating that

                                    (a) the form or forms of such Securities and
                 any  coupons  have  been  established  in  conformity  with the
                 provisions of this Indenture;

                                    (b) the  terms  of such  Securities  and any
                 coupons have been established in conformity with the provisions
                 of this Indenture; and

                                    (c)  such  Securities,   together  with  any
                 coupons  appertaining  thereto,  when  completed by appropriate
                 insertions  and  executed  and  delivered by the Company to the
                 Trustee for  

                                      -16-

                 authentication in accordance with this Indenture, authenticated
                 and delivered by the Trustee in accordance  with this Indenture
                 and issued by the  Company  in the  manner  and  subject to any
                 conditions   specified  in  such   Opinion  of  Counsel,   will
                 constitute legal, valid and binding obligations of the Company,
                 enforceable  in  accordance   with  their  terms,   subject  to
                 applicable  bankruptcy,  insolvency,  reorganization  and other
                 similar laws of general applicability  relating to or affecting
                 the enforcement of creditors'  rights  generally and to general
                 equitable principles; and

                           (ii)  an  Officers'   Certificate  stating  that  all
         conditions  precedent  provided for in this  Indenture  relating to the
         issuance of the  Securities  have been  complied  with and that, to the
         best of the knowledge of the signers of such  certificate,  no Event of
         Default with respect to any of the  Securities  shall have occurred and
         be continuing.

If such  form or terms  have  been so  established,  the  Trustee  shall  not be
required  to  authenticate  such  Securities  if the  issue  of such  Securities
pursuant  to this  Indenture  will  affect the  Trustee's  own  rights,  duties,
obligations  or immunities  under the Securities and this Indenture or otherwise
in a manner which is not reasonably acceptable to the Trustee.

                 Notwithstanding  the  provisions  of  Section  301  and  of the
preceding paragraph, if all the Securities of any series are not to be issued at
one  time,  it shall  not be  necessary  to  deliver  an  Officers'  Certificate
otherwise  required pursuant to Section 301 or a Company Order, or an Opinion of
Counsel or an Officers' Certificate otherwise required pursuant to the preceding
paragraph  at the time of issuance of each  Security  of such  series,  but such
order,  opinion and certificates,  with appropriate  modifications to cover such
future  issuances,  shall be  delivered at or before the time of issuance of the
first Security of such series.

                 Each  Registered  Security  shall  be  dated  the  date  of its
authentication  and each Bearer Security shall be dated as of the date specified
as contemplated by Section 301.

                 No  Security or coupon  shall be entitled to any benefit  under
this Indenture or be valid or obligatory for any purpose unless there appears on
such  Security  or Security to which such coupon  appertains  a  certificate  of
authentication  substantially  in the form  provided for herein duly executed by
the Trustee by manual signature of an authorized  officer,  and such certificate
upon any Security shall be conclusive evidence, and the only evidence, that such
Security has been duly authenticated and delivered  hereunder and is entitled to
the benefits of this Indenture.  Notwithstanding the foregoing,  if any Security
shall have been authenticated and delivered  hereunder but never issued and sold
by the Company,  and the Company  shall deliver such Security to the Trustee for
cancellation as provided in Section 309 together with a written statement (which
need not comply with  Section 102 and need not be  accompanied  by an Opinion of
Counsel)  stating  that such  Security  has never  been  issued  and sold by the
Company,  for all purposes of this Indenture such Security shall be deemed never
to have been  authenticated and delivered  hereunder and shall never be entitled
to the benefits of this Indenture.

                 SECTION 304.  Temporary Securities.

                 (a) Pending the  preparation  of  definitive  Securities of any
series,  the Company  may  execute,  and upon  Company  Order the Trustee  shall
authenticate and deliver, temporary Securities which are printed,  lithographed,
typewritten, mimeographed or otherwise produced, in any authorized denomination,
substantially  of the tenor of the  definitive  Securities in lieu of which they
are issued,  in registered  form, or, if authorized,  in bearer form with one or
more  coupons  or  without  coupons,  and  with  such  appropriate   insertions,
omissions,  substitutions  and other  variations as the officers  executing such
Securities may determine,  as conclusively  evidenced by their execution of such
Securities.  In the case of Securities of any series, such temporary  Securities
may be in global form.

                 Except  in the case of  temporary  Securities  in  global  form
(which  shall be  exchanged in  accordance  with Section  304(b) or as otherwise
provided in or pursuant to a Board Resolution),  if temporary  Securities of any
series are issued,  the Company will cause definitive  Securities of that series
to be prepared without  unreasonable  delay. After the preparation of definitive
Securities  of such series,  the  temporary  Securities  of such series shall be
exchangeable  for  

                                      -17-

definitive  Securities of such series upon surrender of the temporary Securities
of such  series at the office or agency of the Company in a Place of Payment for
that series,  without charge to the Holder.  Upon surrender for  cancellation of
any  one  or  more  temporary  Securities  of  any  series  (accompanied  by any
non-matured  coupons  appertaining  thereto),  the Company shall execute and the
Trustee shall  authenticate  and deliver in exchange  therefor a like  principal
amount of definitive Securities of the same series of authorized  denominations;
provided,  however,  that no definitive  Bearer  Security  shall be delivered in
exchange  for a temporary  Registered  Security;  and  provided  further  that a
definitive Bearer Security shall be delivered in exchange for a temporary Bearer
Security only in compliance  with the conditions set forth in Section 303. Until
so exchanged,  the  temporary  Securities of any series shall in all respects be
entitled to the same benefits under this  Indenture as definitive  Securities of
such series.

                 (b)  Unless  otherwise  provided  in  or  pursuant  to a  Board
Resolution,   this  Section  304(b)  shall  govern  the  exchange  of  temporary
Securities  issued in global form other than through the  facilities  of DTC. If
any such temporary Security is issued in global form, then such temporary global
Security shall,  unless otherwise  provided therein,  be delivered to the London
office of a depositary or common depositary (the "Common  Depositary"),  for the
benefit of Euroclear  and CEDEL,  for credit to the  respective  accounts of the
beneficial  owners of such  Securities  (or to such other  accounts  as they may
direct).

                 Without  unnecessary  delay but in any event not later than the
date  specified in, or determined  pursuant to the terms of, any such  temporary
global Security (the "Exchange Date"),  the Company shall deliver to the Trustee
definitive  Securities,  in aggregate  principal  amount equal to the  principal
amount of such temporary global Security,  executed by the Company.  On or after
the Exchange Date,  such temporary  global  Security shall be surrendered by the
Common Depositary to the Trustee, as the Company's agent for such purpose, to be
exchanged,  in whole or from  time to time in part,  for  definitive  Securities
without charge, and the Trustee shall authenticate and deliver,  in exchange for
each portion of such temporary  global  Security,  an equal aggregate  principal
amount of definitive  Securities of the same series of authorized  denominations
and of like  tenor  as the  portion  of such  temporary  global  Security  to be
exchanged.  The  definitive  Securities to be delivered in exchange for any such
temporary global Security shall be in bearer form,  registered  form,  permanent
global  bearer form or permanent  global  registered  form,  or any  combination
thereof,  as specified as  contemplated  by Section 301, and, if any combination
thereof is so specified, as requested by the beneficial owner thereof; provided,
however,  that,  unless  otherwise  specified in such temporary global Security,
upon such presentation by the Common Depositary,  such temporary global Security
is accompanied by a certificate dated the Exchange Date or a subsequent date and
signed by Euroclear as to the portion of such temporary global Security held for
its account then to be exchanged and a certificate  dated the Exchange Date or a
subsequent  date and signed by CEDEL as to the portion of such temporary  global
Security held for its account then to be  exchanged,  each in the form set forth
in Exhibit  A-2 to this  Indenture  or in such other form as may be  established
pursuant to Section 301; and provided further that definitive  Bearer Securities
shall be delivered in exchange for a portion of a temporary global Security only
in compliance with the requirements of Section 303.

                 Unless  otherwise  specified in such temporary global Security,
the  interest of a  beneficial  owner of  Securities  of a series in a temporary
global Security shall be exchanged for definitive  Securities of the same series
and of like tenor following the Exchange Date when the account holder  instructs
Euroclear or CEDEL,  as the case may be, to request such  exchange on his behalf
and  delivers to Euroclear or CEDEL,  as the case may be, a  certificate  in the
form set forth in Exhibit A-1 to this  Indenture  (or in such other forms as may
be established  pursuant to Section 301), dated no earlier than 15 days prior to
the Exchange  Date,  copies of which  certificate  shall be  available  from the
offices of Euroclear and CEDEL, the Trustee,  any Authenticating Agent appointed
for such series of Securities and each Paying Agent.  Unless otherwise specified
in such  temporary  global  Security,  any such  exchange  shall be made free of
charge to the beneficial owners of such temporary global Security, except that a
Person receiving definitive Securities must bear the cost of insurance, postage,
transportation and the like unless such Person takes delivery of such definitive
Securities in person at the offices of Euroclear or CEDEL. Definitive Securities
in bearer form to be delivered in exchange for any portion of a temporary global
Security shall be delivered only outside the United States.

                 Until exchanged in full as hereinabove provided,  the temporary
Securities  of any series shall in all respects be entitled to the same benefits
under this  Indenture as  definitive  Securities  of the same series and of like
tenor  

                                      -18-

authenticated and delivered  hereunder,  except that, unless otherwise specified
as contemplated by Section 301,  interest payable on a temporary global Security
on an Interest Payment Date for Securities of such series occurring prior to the
applicable  Exchange  Date  shall be  payable  to  Euroclear  and  CEDEL on such
Interest  Payment Date upon  delivery by Euroclear and CEDEL to the Trustee of a
certificate  or  certificates  in the form  set  forth  in  Exhibit  A-2 to this
Indenture  (or in such other  forms as may be  established  pursuant  to Section
301), for credit without further interest on or after such Interest Payment Date
to the  respective  accounts  of persons who are the  beneficial  owners of such
temporary  global  Security  on such  Interest  Payment  Date and who have  each
delivered  to  Euroclear or CEDEL,  as the case may be, a  certificate  dated no
earlier than 15 days prior to the Interest  Payment Date occurring prior to such
Exchange Date in the form set forth as Exhibit A-1 to this Indenture (or in such
other  forms as may be  established  pursuant to Section  301).  Notwithstanding
anything to the contrary herein contained,  the certifications  made pursuant to
this paragraph shall satisfy the certification requirements of the preceding two
paragraphs of this Section 304 (b) and of the third  paragraph of Section 303 of
this Indenture and the interests of the Persons who are the beneficial owners of
a temporary  global Security with respect to which such  certification  was made
will be exchanged for definitive Securities of the same series and of like tenor
on the Exchange Date or the date of  certification if such date occurs after the
Exchange Date, without further act or deed by such beneficial owners.  Except as
otherwise provided in this paragraph, no payments of principal or interest owing
with respect to a beneficial  interest in a temporary  global  Security  will be
made unless and until such interest in such temporary global Security shall have
been  exchanged  for an  interest  in a  definitive  Security.  Any  interest so
received  by  Euroclear  and  CEDEL  and not paid as  herein  provided  shall be
returned to the Trustee prior to the expiration of two years after such Interest
Payment Date in order to be repaid to the Company.

                 SECTION  305.   Registration,   Registration  of  Transfer  and
Exchange.  The Company shall cause to be kept at the  Corporate  Trust Office of
the  Trustee or in any  office or agency of the  Company in a Place of Payment a
register for each series of Securities (the registers  maintained in such office
or in any such  office or  agency of the  Company  in a Place of  Payment  being
herein sometimes referred to collectively as the "Security  Register") in which,
subject to such  reasonable  regulations as it may prescribe,  the Company shall
provide for the  registration  of  Registered  Securities  and of  transfers  of
Registered  Securities.  The Security  Register  shall be in written form or any
other form  capable of being  converted  into  written  form within a reasonable
time. The Trustee,  at its Corporate Trust Office, is hereby initially appointed
"Security  Registrar" for the purpose of registering  Registered  Securities and
transfers of Registered Securities on such Security Register as herein provided.
In the event that the Trustee  shall cease to be  Security  Registrar,  it shall
have the right to examine the Security Register at all reasonable times.

                 Subject to the  provisions of this Section 305, upon  surrender
for  registration  of transfer of any  Registered  Security of any series at any
office or agency of the  Company  in a Place of  Payment  for that  series,  the
Company shall execute,  and the Trustee shall  authenticate and deliver,  in the
name of the  designated  transferee or  transferees,  one or more new Registered
Securities of the same series,  of any  authorized  denominations  and of a like
aggregate principal amount, bearing a number not contemporaneously  outstanding,
and containing identical terms and provisions.

                 Subject to the provisions of this Section 305, at the option of
the  Holder,  Registered  Securities  of any series may be  exchanged  for other
Registered  Securities of the same series,  of any  authorized  denomination  or
denominations  and of a like aggregate  principal amount,  containing  identical
terms  and  provisions,  upon  surrender  of  the  Registered  Securities  to be
exchanged at any such office or agency.  Whenever any such Registered Securities
are so  surrendered  for exchange,  the Company shall  execute,  and the Trustee
shall  authenticate  and deliver,  the  Registered  Securities  which the Holder
making the  exchange is entitled to receive.  Unless  otherwise  specified  with
respect to any series of  Securities  as  contemplated  by Section  301,  Bearer
Securities may not be issued in exchange for Registered Securities.

                 If (but only if) permitted by the applicable  Board  Resolution
and (subject to Section 303) set forth in the applicable Officers'  Certificate,
or in any indenture  supplemental  hereto,  delivered as contemplated by Section
301,  at the  option of the  Holder,  Bearer  Securities  of any  series  may be
exchanged  for  Registered  Securities  of the  same  series  of any  authorized
denominations and of a like aggregate principal amount and tenor, upon surrender
of the Bearer Securities to be exchanged at any such office or agency,  with all
unmatured  coupons and all matured coupons in default 

                                      -19-

thereto  appertaining.  If the Holder of a Bearer  Security is unable to produce
any such  unmatured  coupon or coupons or matured  coupon or coupons in default,
any such  permitted  exchange  may be  effected  if the  Bearer  Securities  are
accompanied by payment in funds  acceptable to the Company in an amount equal to
the face amount of such  missing  coupon or coupons,  or the  surrender  of such
missing  coupon or coupons may be waived by the Company and the Trustee if there
is furnished to them such security or indemnity as they may require to save each
of them and any Paying Agent harmless. If thereafter the Holder of such Security
shall  surrender to any Paying Agent any such missing coupon in respect of which
such a payment  shall have been made,  such Holder  shall be entitled to receive
the  amount of such  payment;  provided,  however,  that,  except  as  otherwise
provided in Section 1002, interest  represented by coupons shall be payable only
upon  presentation and surrender of those coupons at an office or agency located
outside  the United  States.  Notwithstanding  the  foregoing,  in case a Bearer
Security  of any  series  is  surrendered  at any such  office  or  agency  in a
permitted  exchange for a Registered  Security of the same series and like tenor
after the close of business  at such office or agency on (i) any Regular  Record
Date and before the opening of business at such office or agency on the relevant
Interest Payment Date, or (ii) any Special Record Date and before the opening of
business at such office or agency on the  related  proposed  date for payment of
Defaulted Interest, such Bearer Security shall be surrendered without the coupon
relating to such Interest Payment Date or proposed date for payment, as the case
may be, and  interest  or  Defaulted  Interest,  as the case may be, will not be
payable on such Interest Payment Date or proposed date for payment,  as the case
may be, in respect of the Registered Security issued in exchange for such Bearer
Security,  but will be  payable  only to the Holder of such  coupon  when due in
accordance with the provisions of this Indenture. Whenever any Bearer Securities
are so  surrendered  for exchange,  the Company shall  execute,  and the Trustee
shall  authenticate  and deliver,  the  Securities  which the Holder  making the
exchange is entitled to receive.

                 Notwithstanding the foregoing, except as otherwise specified as
contemplated by Section 301, any permanent global Security shall be exchangeable
only as provided in this paragraph.  If the depositary for any permanent  global
Security is DTC, then, unless the terms of such global Security expressly permit
such  global  Security  to be  exchanged  in  whole  or in part  for  definitive
Securities, a global Security may be transferred, in whole but not in part, only
to a nominee of DTC, or by a nominee of DTC to DTC, or to a successor to DTC for
such global Security selected or approved by the Company or to a nominee of such
successor  to DTC. If at any time DTC  notifies the Company that it is unwilling
or unable to  continue  as  depositary  for the  applicable  global  Security or
Securities or if at any time DTC ceases to be a clearing agency registered under
the  Securities  Exchange Act of 1934, as amended,  if so required by applicable
law or regulation, the Company shall appoint a successor depositary with respect
to such global  Security or Securities.  If (x) a successor  depositary for such
global  Security or Securities  is not  appointed by the Company  within 90 days
after the Company  receives such notice or becomes aware of such  unwillingness,
inability  or  ineligibility,  (y) an  Event  of  Default  has  occurred  and is
continuing and the beneficial owners representing a majority in principal amount
of the applicable  series of Securities  represented by such global  Security or
Securities  advise DTC to cease acting as depositary for such global Security or
Securities or (z) the Company,  in its sole  discretion,  determines at any time
that all Outstanding  Securities (but not less than all) of any series issued or
issuable  in the  form of one or more  global  Securities  shall  no  longer  be
represented  by such global  Security  or  Securities,  then the  Company  shall
execute, and the Trustee shall authenticate and deliver,  definitive  Securities
of like  series,  rank,  tenor  and  terms in  definitive  form in an  aggregate
principal  amount  equal to the  principal  amount of such  global  Security  or
Securities.  If any  beneficial  owner  of an  interest  in a  permanent  global
Security is otherwise  entitled to exchange such interest for Securities of such
series and of like tenor and  principal  amount of another  authorized  form and
denomination,  as specified as contemplated by Section 301 and provided that any
applicable  notice  provided in the permanent  global  Security  shall have been
given,  then  without  unnecessary  delay  but in any  event no  later  than the
earliest  date on which such  interest may be so  exchanged,  the Company  shall
execute, and the Trustee shall authenticate and deliver,  definitive  Securities
in aggregate  principal  amount equal to the principal amount of such beneficial
owner's  interest in such permanent  global  Security.  On or after the earliest
date on which such interests may be so exchanged, such permanent global Security
shall be  surrendered  for exchange by DTC or such other  depositary as shall be
specified  in the Company  Order with  respect  thereto to the  Trustee,  as the
Company's agent for such purpose; provided,  however, that no such exchanges may
occur  during a period  beginning  at the opening of business 15 days before any
selection of  Securities  to be redeemed  and ending on the relevant  Redemption
Date if the Security for which exchange is requested may be among those selected
for  redemption;  and  provided  further  that no Bearer  Security  delivered 

                                      -20-

in exchange  for a portion of a  permanent  global  Security  shall be mailed or
otherwise  delivered  to any  location  in the United  States.  If a  Registered
Security is issued in exchange  for any portion of a permanent  global  Security
after the close of business at the office or agency where such  exchange  occurs
on (i) any Regular Record Date and before the opening of business at such office
or agency on the relevant Interest Payment Date, or (ii) any Special Record Date
and  before the  opening of  business  at such  office or agency on the  related
proposed date for payment of Defaulted Interest, interest or Defaulted Interest,
as the case  may be,  will  not be  payable  on such  Interest  Payment  Date or
proposed  date for  payment,  as the case may be, in respect of such  Registered
Security, but will be payable on such Interest Payment Date or proposed date for
payment,  as the case may be, only to the Person to whom  interest in respect of
such portion or such permanent global Security is payable in accordance with the
provisions of this Indenture.

                 All  Securities  issued  upon any  registration  of transfer or
exchange of Securities shall be the valid obligations of the Company, evidencing
the same debt,  and entitled to the same benefits under this  Indenture,  as the
Securities surrendered upon such registration of transfer or exchange.

                 Every   Registered   Security   presented  or  surrendered  for
registration of transfer or for exchange or redemption  shall (if so required by
the Company or the Security Registrar) be duly endorsed,  or be accompanied by a
written  instrument  of  transfer  in form  satisfactory  to the Company and the
Security  Registrar,  duly  executed by the Holder  thereof or his attorney duly
authorized in writing.

                 No  service  charge  shall  be  made  for any  registration  of
transfer or exchange of Securities, but the Company may require payment of a sum
sufficient to cover any tax or other governmental  charge that may be imposed in
connection with any  registration  of transfer or exchange of Securities,  other
than  exchanges  pursuant to Section 304,  906,  1107 or 1305 not  involving any
transfer.

                 The  Company  or  the  Trustee,  as  applicable,  shall  not be
required (i) to issue, register the transfer of or exchange any Security if such
Security may be among those selected for redemption during a period beginning at
the  opening of  business  15 days  before  selection  of the  Securities  to be
redeemed  under  Section 1103 and ending at the close of business on (A) if such
Securities are issuable only as Registered Securities, the day of the mailing of
the relevant  notice of redemption  and (B) if such  Securities  are issuable as
Bearer  Securities,  the day of the first  publication of the relevant notice of
redemption or, if such Securities are also issuable as Registered Securities and
there is no publication,  the mailing of the relevant  notice of redemption,  or
(ii) to register the transfer of or exchange any Registered Security so selected
for  redemption  in  whole  or in part,  except,  in the case of any  Registered
Security to be redeemed in part,  the  portion  thereof not to be  redeemed,  or
(iii) to exchange  any Bearer  Security so selected for  redemption  except that
such a Bearer Security may be exchanged for a Registered Security of that series
and  of  like  tenor;   provided  that  such   Registered   Security   shall  be
simultaneously  surrendered  for  redemption,  or (iv) to  issue,  register  the
transfer of or exchange any Security which has been surrendered for repayment at
the option of the Holder, except that portion, if any, of such Security which is
not to be so repaid.

                 SECTION 306. Mutilated,  Destroyed, Lost and Stolen Securities.
If any mutilated Security or a Security with a mutilated coupon  appertaining to
it is surrendered to the Trustee or the Company, together with, in proper cases,
such  security or  indemnity as may be required by the Company or the Trustee to
save each of them or any agent of either of them  harmless,  the  Company  shall
execute and the Trustee shall  authenticate  and deliver in exchange  therefor a
new Security of the same series and principal amount, containing identical terms
and  provisions  and bearing a number not  contemporaneously  outstanding,  with
coupons  corresponding to the coupons,  if any,  appertaining to the surrendered
Security.

                 If there shall be  delivered  to the Company and to the Trustee
(i)  evidence to their  satisfaction  of the  destruction,  loss or theft of any
Security or coupon,  and (ii) such  security or  indemnity as may be required by
them to save each of them and any agent of either of them harmless, then, in the
absence of written  notice to the Company or the Trustee  that such  Security or
coupon has been acquired by a bona fide purchaser, the Company shall execute and
upon its request the Trustee shall authenticate and deliver, in lieu of any such
destroyed,  lost or stolen  Security or in exchange  for the Security to which a
destroyed,  lost or stolen coupon  appertains (with all appurtenant  coupons not
destroyed,  lost or stolen),  a new  Security  of the same series and  principal
amount,  containing  identical  terms and  

                                      -21-

provisions and bearing a number not contemporaneously  outstanding, with coupons
corresponding to the coupons,  if any,  appertaining to such destroyed,  lost or
stolen  Security  or to the  Security  to which such  destroyed,  lost or stolen
coupon appertains.

                 Notwithstanding  the provisions of the previous two paragraphs,
in case any such  mutilated,  destroyed,  lost or stolen  Security or coupon has
become or is about to become due and payable, the Company in its discretion may,
instead of issuing a new Security, with coupons corresponding to the coupons, if
any, appertaining to such destroyed,  lost or stolen Security or to the Security
to which such destroyed, lost or stolen coupon appertains,  pay such Security or
coupon;  provided,  however, that payment of principal of (and premium, if any),
any interest on and any  Additional  Amounts with respect to, Bearer  Securities
shall,  except as  otherwise  provided in Section  1002,  be payable  only at an
office or agency  located  outside  the  United  States  and,  unless  otherwise
specified as  contemplated  by Section  301,  any interest on Bearer  Securities
shall  be  payable  only  upon   presentation   and  surrender  of  the  coupons
appertaining thereto.

                 Upon the issuance of any new Security  under this Section,  the
Company may require  the payment of a sum  sufficient  to cover any tax or other
governmental  charge  that may be  imposed  in  relation  thereto  and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

                 Every new  Security  of any series  with its  coupons,  if any,
issued  pursuant  to  this  Section  in lieu of any  destroyed,  lost or  stolen
Security,  or in exchange  for a Security to which a  destroyed,  lost or stolen
coupon  appertains,   shall  constitute  an  original   additional   contractual
obligation of the Company, whether or not the destroyed, lost or stolen Security
and its coupons, if any, or the destroyed, lost or stolen coupon shall be at any
time  enforceable  by anyone,  and shall be entitled to all the benefits of this
Indenture equally and proportionately  with any and all other Securities of that
series and their coupons, if any, duly issued hereunder.

                 The provisions of this Section are exclusive and shall preclude
(to the  extent  lawful)  all other  rights  and  remedies  with  respect to the
replacement  or payment of mutilated,  destroyed,  lost or stolen  Securities or
coupons.

                 SECTION 307.  Payment of Interest;  Interest Rights  Preserved.
Except  as  otherwise  specified  with  respect  to a series  of  Securities  in
accordance  with the  provisions  of Section  301,  interest  on any  Registered
Security that is payable,  and is  punctually  paid or duly provided for, on any
Interest  Payment  Date shall be paid to the Person in whose name that  Security
(or one or more  Predecessor  Securities) is registered at the close of business
on the  Regular  Record  Date for such  interest  at the office or agency of the
Company maintained for such purpose pursuant to Section 1002; provided, however,
that  each  installment  of  interest  on  any  Registered  Security  may at the
Company's option be paid by (i) mailing a check for such interest, payable to or
upon the written order of the Person entitled  thereto  pursuant to Section 308,
to the  address of such  Person as it appears on the  Security  Register or (ii)
transfer to an account maintained by the payee located inside the United States.

                 Unless  otherwise  provided as contemplated by Section 301 with
respect to the Securities of any series, payment of interest may be made, in the
case of a Bearer  Security,  by transfer to an account  maintained  by the payee
with a bank located outside the United States.

                 Unless otherwise provided as contemplated by Section 301, every
permanent  global  Security will provide that interest,  if any,  payable on any
Interest  Payment Date will be paid to DTC,  Euroclear and/or CEDEL, as the case
may be, with respect to that portion of such permanent  global Security held for
its account by Cede & Co. or the Common Depositary,  as the case may be, for the
purpose  of  permitting  such  party to credit the  interest  received  by it in
respect of such  permanent  global  Security to the  accounts of the  beneficial
owners thereof.

                 In case a Bearer  Security  of any  series  is  surrendered  in
exchange  for a  Registered  Security of such series after the close of business
(at an office or agency in a Place of Payment  for such  series) on any  Regular
Record Date and before the opening of business (at such office or agency) on the
next succeeding Interest Payment Date, such Bearer Security shall be surrendered
without the coupon relating to such Interest  Payment Date and interest will not
be 

                                      -22-

payable on such  Interest  Payment  Date in respect of the  Registered  Security
issued in exchange  for such Bearer  Security,  but will be payable  only to the
Holder  of such  coupon  when  due in  accordance  with the  provisions  of this
Indenture.

                 Except  as  otherwise  specified  with  respect  to a series of
Securities in accordance with the provisions of Section 301, any interest on any
Registered Security of any series that is payable, but is not punctually paid or
duly  provided  for, on any  Interest  Payment Date  (herein  called  "Defaulted
Interest") shall forthwith cease to be payable to the registered  Holder thereof
on the relevant  Regular  Record Date by virtue of having been such Holder,  and
such  Defaulted  Interest  may be paid by the  Company,  at its election in each
case, as provided in clause (1) or (2) below:

                           (1) The  Company  may  elect to make  payment  of any
         Defaulted  Interest  to the  Persons  in  whose  names  the  Registered
         Securities of such series (or their respective Predecessor  Securities)
         are  registered  at the close of business on a Special  Record Date for
         the  payment of such  Defaulted  Interest,  which shall be fixed in the
         following  manner.  The Company  shall notify the Trustee in writing of
         the amount of Defaulted Interest proposed to be paid on each Registered
         Security of such  series and the date of the  proposed  payment  (which
         shall not be less than 20 days after  such  notice is  received  by the
         Trustee),  and at the same  time the  Company  shall  deposit  with the
         Trustee an amount of money in the currency or currencies, currency unit
         or units or composite currency or currencies in which the Securities of
         such  series are payable  (except as  otherwise  specified  pursuant to
         Section 301 for the  Securities  of such series) equal to the aggregate
         amount  proposed  to be paid in respect of such  Defaulted  Interest or
         shall make arrangements satisfactory to the Trustee for such deposit on
         or prior to the date of the proposed payment, such money when deposited
         to be held in trust for the  benefit of the  Persons  entitled  to such
         Defaulted  Interest as in this clause  provided.  Thereupon the Trustee
         shall fix a  Special  Record  Date for the  payment  of such  Defaulted
         Interest which shall not be more than 15 days and not less than 10 days
         prior to the date of the  proposed  payment  and not less  than 10 days
         after the receipt by the Trustee of the notice of the proposed payment.
         The Trustee shall  promptly  notify the Company of such Special  Record
         Date and,  in the name and at the expense of the  Company,  shall cause
         notice of the  proposed  payment  of such  Defaulted  Interest  and the
         Special Record Date therefor to be mailed, first-class postage prepaid,
         to each Holder of  Registered  Securities of such series at his address
         as it appears in the  Security  Register not less than 10 days prior to
         such Special  Record Date. The Trustee may, in its  discretion,  in the
         name and at the expense of the  Company,  cause a similar  notice to be
         published  at least once in an  Authorized  Newspaper  in each Place of
         Payment,  but such publications  shall not be a condition  precedent to
         the  establishment of such Special Record Date.  Notice of the proposed
         payment of such Defaulted Interest and the Special Record Date therefor
         having been mailed as aforesaid,  such Defaulted Interest shall be paid
         to the Persons in whose names the Registered  Securities of such series
         (or their  respective  Predecessor  Securities)  are  registered at the
         close of  business on such  Special  Record Date and shall no longer be
         payable pursuant to the following clause (2). In case a Bearer Security
         of any series is surrendered  for transfer or exchange at the office or
         agency  in a Place  of  Payment  for such  series  after  the  close of
         business at such office or agency on any Special Record Date and before
         the  opening  of  business  at such  office or  agency  on the  related
         proposed date for payment of Defaulted  Interest,  such Bearer Security
         shall be surrendered  without the coupon relating to such proposed date
         of payment and Defaulted  Interest will not be payable on such proposed
         date of  payment  in  respect  of the  Registered  Security  issued  in
         exchange  for such  Bearer  Security,  but will be payable  only to the
         Holder of such coupon when due in  accordance  with the  provisions  of
         this Indenture.

                           (2) The  Company  may make  payment of any  Defaulted
         Interest on the Registered Securities of any series in any other lawful
         manner  not  inconsistent  with  the  requirements  of  any  securities
         exchange on which such  Securities may be listed,  and upon such notice
         as may be required by such  exchange,  if,  after  notice  given by the
         Company to the Trustee of the proposed payment pursuant to this clause,
         such manner of payment shall be deemed practicable by the Trustee.

                 Subject to the foregoing provisions of this Section and Section
305, each Security  delivered under this Indenture upon registration of transfer
of or in exchange for or in lieu of any other Security shall carry the rights to
interest  accrued and unpaid,  and to accrue,  which were  carried by such other
Security.
                                      -23-

                 SECTION 308. Persons Deemed Owners. Prior to due presentment of
a Registered Security for registration of transfer, the Company, the Trustee and
any agent of the  Company or the Trustee may treat the Person in whose name such
Registered  Security is registered as the owner of such Security for the purpose
of  receiving  payment of principal of (and  premium,  if any),  and (subject to
Sections 305 and 307)  interest on, such  Registered  Security and for all other
purposes  whatsoever,  whether or not such Registered  Security is overdue,  and
neither  the  Company,  the  Trustee nor any agent of the Company or the Trustee
shall be affected by notice to the contrary.

                 Title  to any  Bearer  Security  and any  coupons  appertaining
thereto  shall pass by delivery.  The Company,  the Trustee and any agent of the
Company  or the  Trustee  may treat the Holder of any  Bearer  Security  and the
Holder of any coupon as the  absolute  owner of such  Security or coupon for the
purpose of  receiving  payment  thereof or on account  thereof and for all other
purposes  whatsoever,  whether or not such  Security or coupon is  overdue,  and
neither  the  Company,  the  Trustee nor any agent of the Company or the Trustee
shall be affected by notice to the contrary.

                 None of the  Company,  the  Trustee,  any  Paying  Agent or the
Security  Registrar will have any  responsibility or liability for any aspect of
the  records  relating to or payments  made on account of  beneficial  ownership
interests  of a  Security  in global  form or for  maintaining,  supervising  or
reviewing any records relating to such beneficial ownership interests.

                 Notwithstanding  the  foregoing,  with  respect  to any  global
Security, nothing herein shall prevent the Company, the Trustee, or any agent of
the Company or the  Trustee,  from giving  effect to any written  certification,
proxy or other  authorization  furnished by any  depositary,  as a Holder,  with
respect to such global Security or impair, as between such depositary and owners
of  beneficial  interests in such global  Security,  the  operation of customary
practices  governing  the  exercise  of the  rights of such  depositary  (or its
nominee) as Holder of such global Security.

                 SECTION  309.   Cancellation.   All   Securities   and  coupons
surrendered  for  payment,  redemption,  repayment  at the option of the Holder,
registration  of transfer or  exchange  or for credit  against any sinking  fund
payment shall, if surrendered to any Person other than the Trustee, be delivered
to the Trustee,  and any such  Securities and coupons and Securities and coupons
surrendered  directly  to the  Trustee  for any such  purpose  shall be promptly
cancelled  by it.  The  Company  may at any  time  deliver  to the  Trustee  for
cancellation any Securities  previously  authenticated  and delivered  hereunder
which the Company may have acquired in any manner whatsoever, and may deliver to
the  Trustee  (or  to  any  other  Person  for  delivery  to  the  Trustee)  for
cancellation any Securities previously authenticated hereunder which the Company
has not issued and sold,  and all  Securities  so  delivered  shall be  promptly
cancelled by the Trustee. If the Company shall so acquire any of the Securities,
however,  such acquisition  shall not operate as a redemption or satisfaction of
the  indebtedness  represented by such Securities  unless and until the same are
surrendered   to  the  Trustee  for   cancellation.   No  Securities   shall  be
authenticated in lieu of or in exchange for any Securities cancelled as provided
in this  Section,  except as expressly  permitted by this  Indenture.  Cancelled
Securities and coupons held by the Trustee shall be destroyed by the Trustee and
the Trustee  shall  deliver a certificate  of such  destruction  to the Company,
unless by a Company Order the Company directs their return to it.

                 SECTION  310.  Computation  of  Interest.  Except as  otherwise
specified  as  contemplated  by Section 301 with  respect to  Securities  of any
series, interest on the Securities of each series shall be computed on the basis
of a 360-day year consisting of twelve 30-day months.


                                  ARTICLE FOUR

                           SATISFACTION AND DISCHARGE

                 SECTION 401.  Satisfaction  and  Discharge of  Indenture.  This
Indenture  shall upon Company Request cease to be of further effect with respect
to any series of Securities  specified in such Company Request (except as to any
surviving  rights of  registration of transfer or exchange of Securities of such
series  herein  expressly  provided  for and 

                                      -24-

any right to receive Additional  Amounts,  as provided in Section 1007), and the
Trustee,  upon  receipt of a Company  Order,  and at the expense of the Company,
shall execute proper  instruments  acknowledging  satisfaction  and discharge of
this Indenture as to such series when

                           (1)  either

                                    (A)   all    Securities   of   such   series
                 theretofore  authenticated  and delivered  and all coupons,  if
                 any,  appertaining thereto (other than (i) coupons appertaining
                 to Bearer  Securities  surrendered  for exchange for Registered
                 Securities and maturing after such exchange, whose surrender is
                 not  required or has been  waived as  provided in Section  305,
                 (ii)  Securities  and  coupons of such  series  which have been
                 destroyed,  lost or stolen and which have been replaced or paid
                 as provided  in Section  306,  (iii)  coupons  appertaining  to
                 Securities   called  for  redemption  and  maturing  after  the
                 relevant  Redemption  Date,  whose surrender has been waived as
                 provided in Section 1106,  and (iv)  Securities  and coupons of
                 such  series  for  whose  payment  money has  theretofore  been
                 deposited  in  trust  or  segregated  and  held in trust by the
                 Company and thereafter repaid to the Company or discharged from
                 such trust, as provided in Section 1003) have been delivered to
                 the Trustee for cancellation; or

                                    (B) all  Securities  of such  series and, in
                 the  case  of (i)  or  (ii)  below,  any  coupons  appertaining
                 thereto,   not   theretofore   delivered  to  the  Trustee  for
                 cancellation

                                            (i)      have    become    due   and
                                                     payable, or

                                            (ii)     will become due and payable
                                                     at  their  Stated  Maturity
                                                     within one year, or

                                            (iii)    if redeemable at the option
                                                     of the  Company,  are to be
                                                     called    for    redemption
                                                     within   one   year   under
                                                     arrangements   satisfactory
                                                     to  the   Trustee  for  the
                                                     giving    of    notice   of
                                                     redemption  by the  Trustee
                                                     in  the  name,  and  at the
                                                     expense, of the Company,

                 and the Company,  in the case of (i), (ii) or (iii) above,  has
                 irrevocably  deposited  or  caused  to be  deposited  with  the
                 Trustee  as funds in trust  for such  purpose  an amount in the
                 currency or  currencies,  currency  unit or units or  composite
                 currency or currencies  in which the  Securities of such series
                 are  payable,  sufficient  to  pay  and  discharge  the  entire
                 indebtedness   on  such   Securities   and  such   coupons  not
                 theretofore  delivered  to the  Trustee for  cancellation,  for
                 principal  (and  premium,   if  any)  and  interest,   and  any
                 Additional  Amounts with respect  thereto,  to the date of such
                 deposit  (in the case of  Securities  which have become due and
                 payable) or to the Stated  Maturity or Redemption  Date, as the
                 case may be;

                           (2) the  Company  has paid or  caused  to be paid all
         other sums payable hereunder by the Company; and

                           (3) the  Company  has  delivered  to the  Trustee  an
         Officers'  Certificate and an Opinion of Counsel, each stating that all
         conditions  precedent  herein provided for relating to the satisfaction
         and  discharge of this  Indenture as to such series have been  complied
         with.

The obligations of the Company to the Trustee and any predecessor  Trustee under
Section 606, the  obligations of the Company to any  Authenticating  Agent under
Section 611 and, if money shall have been deposited with and held by the Trustee
pursuant to subclause (B) of clause (1) of this Section,  the obligations of the
Trustee under  Section 402 and the last  paragraph of Section 1003 shall survive
the satisfaction and discharge of this Indenture.

                                      -25-

                 SECTION  402.  Application  of  Trust  Funds.  Subject  to  the
provisions of the last paragraph of Section 1003,  all money  deposited with the
Trustee  pursuant  to Section  401 shall be held in trust and  applied by it, in
accordance  with  the  provisions  of  the  Securities,  the  coupons  and  this
Indenture,  to  the  payment,  either  directly  or  through  any  Paying  Agent
(including  the  Company  acting as its own  Paying  Agent) as the  Trustee  may
determine,  to the Persons entitled thereto,  of the principal (and premium,  if
any), and any interest and  Additional  Amounts for whose payment such money has
been  deposited  with or  received  by the  Trustee,  but such money need not be
segregated from other funds except to the extent required by law.


                                  ARTICLE FIVE

                                    REMEDIES

                 SECTION 501.  Events of Default.  "Event of Default",  wherever
used herein with respect to any particular  series of Securities,  means any one
of the  following  events  (whatever  the reason  for such Event of Default  and
whether or not it shall be voluntary or  involuntary or be effected by operation
of law or pursuant to any  judgment,  decree or order of any court or any order,
rule or regulation of any administrative or governmental body):

                           (1)  default in the payment of any  interest  upon or
         any  Additional  Amounts  payable in respect  of any  Security  of that
         series or of any  coupon  appertaining  thereto,  when  such  interest,
         Additional  Amounts or coupon becomes due and payable,  and continuance
         of such default for a period of 30 days; or

                           (2)  default in the payment of the  principal  of (or
         premium,  if any,  on) any  Security of that series when it becomes due
         and payable at its Maturity; or

                           (3)  default  in  the  deposit  of any  sinking  fund
         payment,  when and as due by the terms of any  Security of that series;
         or

                           (4) default in the  performance of, or breach of, any
         covenant  of the  Company in this  Indenture  (other  than a covenant a
         default  in whose  performance  or whose  breach is  elsewhere  in this
         Section specifically dealt with or which has been expressly included in
         this Indenture  solely for the benefit of a series of Securities  other
         than that  series),  and  continuance  of such  default or breach for a
         period  of 60 days  after  there  has  been  given,  by  registered  or
         certified mail, to the Company by the Trustee or to the Company and the
         Trustee by the  Holders of at least a majority in  principal  amount of
         the Outstanding  Securities of that series a written notice  specifying
         such default or breach and requiring it to be remedied and stating that
         such notice is a "Notice of Default" hereunder; or

                           (5) a  default  under any  bond,  debenture,  note or
         other evidence of indebtedness  of the Company,  or under any mortgage,
         indenture or other instrument of the Company  (including a default with
         respect to Securities of any series other than that series) under which
         there may be issued or by which there may be secured  any  indebtedness
         of the  Company  (or by any  Subsidiary,  the  repayment  of which  the
         Company has guaranteed or for which the Company is directly responsible
         or liable as obligor  or  guarantor),  whether  such  indebtedness  now
         exists or shall hereafter be created,  which default shall constitute a
         failure to pay an aggregate principal amount exceeding  $___________ of
         such  indebtedness  when due and payable  after the  expiration  of any
         applicable grace period with respect thereto and shall have resulted in
         such   indebtedness  in  an  aggregate   principal   amount   exceeding
         $____________  becoming or being  declared due and payable prior to the
         date on which it would  otherwise have become due and payable,  without
         such indebtedness  having been discharged,  or such acceleration having
         been  rescinded  or  annulled,  within a period of 10 days after  there
         shall have been given,  by registered or certified mail, to the Company
         by the  Trustee or to the  Company and the Trustee by the Holders of at
         least a majority in principal  amount of the Outstanding  Securities of
         that series a written notice  specifying such default and requiring the
         Company  to cause  such  indebtedness  to be  

                                      -26-

         discharged or cause such  acceleration  to be rescinded or annulled and
         stating that such notice is a "Notice of Default" hereunder; or

                           (6)  the  Company  or  any   Significant   Subsidiary
         pursuant to or within the meaning of any Bankruptcy Law:

                                    (A) commences a voluntary case,

                                    (B)  consents  to the  entry of an order for
                 relief against it in an involuntary case,

                                    (C)  consents  to  the   appointment   of  a
                 Custodian  of it  or  for  all  or  substantially  all  of  its
                 property, or

                                    (D)  makes  a  general  assignment  for  the
                 benefit of its creditors; or

                           (7) a court of competent jurisdiction enters an order
         or decree under any Bankruptcy Law that:

                                    (A) is for relief against the Company or any
                 Significant Subsidiary in an involuntary case,

                                    (B)  appoints a Custodian  of the Company or
                 any Significant  Subsidiary or for all or substantially  all of
                 either of its property, or

                                    (C) orders the liquidation of the Company or
                 any Significant Subsidiary,

         and the order or decree remains unstayed and in effect for 60 days; or

                           (8) any other Event of Default  provided with respect
         to Securities of that series.

As used in this Section 501, the term "Bankruptcy Law" means Title 11, U.S. Code
or any  similar  Federal  or State law for the  relief of  debtors  and the term
"Custodian" means any receiver,  trustee, assignee,  liquidator or other similar
official under any Bankruptcy Law.

                 SECTION  502.   Acceleration   of  Maturity;   Rescission   and
Annulment.  If an Event of Default with respect to  Securities  of any series at
the time  Outstanding  occurs and is continuing  (other than an Event of Default
described in Section 501(6) or 501(7)),  then and in every such case the Trustee
or the Holders of at least 25% in principal amount of the Outstanding Securities
of that series may declare the  principal  (or, if any  Securities  are Original
Issue Discount Securities or Indexed  Securities,  such portion of the principal
as may be specified in the terms  thereof) of all the  Securities of that series
to be due and payable immediately, by a notice in writing to the Company (and to
the  Trustee  if given by the  Holders),  and  upon  any such  declaration  such
principal or specified portion thereof shall become immediately due and payable.
If an Event of Default described in Section 501(6) or 501(7) with respect to any
series of Securities at the time outstanding occurs, the principal amount of all
of the  Securities  of that series (or, in the case of any such  Original  Issue
Discount Securities or Indexed Securities,  such portion of the principal as may
be specified in the terms thereof) will automatically, and without any action by
the Trustee or any Holder thereof, become immediately due and payable.

                 At any time  after  such a  declaration  of  acceleration  with
respect to  Securities  of any  series  has been made and  before a judgment  or
decree  for  payment  of the  money  due has been  obtained  by the  Trustee  as
hereinafter  in this  Article  provided,  the Holders of a majority in principal
amount of the  Outstanding  Securities of that series,  by written notice to the
Company  and the  Trustee,  may  rescind  and  annul  such  declaration  and its
consequences if:

                                      -27-

                           (1) the  Company  has  paid  or  deposited  with  the
         Trustee  a sum  sufficient  to pay in the  currency,  currency  unit or
         composite  currency in which the  Securities of such series are payable
         (except  as  otherwise  specified  pursuant  to  Section  301  for  the
         Securities of such series):

                                    (A) all overdue  installments of interest on
                 and  any   Additional   Amounts   payable  in  respect  of  all
                 Outstanding Securities of that series and any related coupons,

                                    (B) the principal of (and  premium,  if any,
                 on) any Outstanding Securities of that series which have become
                 due otherwise  than by such  declaration  of  acceleration  and
                 interest  thereon at the rate or rates borne by or provided for
                 in such Securities,

                                    (C) to  the  extent  that  payment  of  such
                 interest  is lawful,  interest  upon  overdue  installments  of
                 interest and any Additional  Amounts at the rate or rates borne
                 by or provided for in such Securities, and

                                    (D) all sums paid or advanced by the Trustee
                 hereunder   and   the   reasonable   compensation,    expenses,
                 disbursements  and  advances  of the  Trustee,  its  agents and
                 counsel; and

                           (2) all Events of Default with respect to  Securities
         of that  series,  other than the  nonpayment  of the  principal  of (or
         premium,  if any) or interest on  Securities  of that series which have
         become due solely by such declaration of acceleration,  have been cured
         or waived as provided in Section 513.

No such  rescission  shall  affect  any  subsequent  default or impair any right
consequent thereon.

                 SECTION  503.   Collection  of   Indebtedness   and  Suits  for
Enforcement by Trustee. The Company covenants that if:

                           (1) default is made in the payment of any installment
         of  interest or  Additional  Amounts,  if any,  on any  Security of any
         series and any related  coupon when such interest or Additional  Amount
         becomes due and payable and such default  continues  for a period of 30
         days, or

                           (2) default is made in the  payment of the  principal
         of (or premium, if any, on) any Security of any series at its Maturity,

then the Company will, upon demand of the Trustee,  pay to the Trustee,  for the
benefit of the Holders of such Securities of such series and coupons,  the whole
amount then due and payable on such  Securities  and coupons for principal  (and
premium, if any) and interest and Additional Amounts thereon, with interest upon
any overdue  principal (and premium,  if any) and, to the extent that payment of
such interest shall be legally  enforceable,  upon any overdue  installments  of
interest or Additional Amounts thereon, if any, at the rate or rates borne by or
provided for in such Securities,  and, in addition thereto,  such further amount
as shall be sufficient to cover the costs and expenses of collection,  including
the  reasonable  compensation,  expenses,  disbursements  and  advances  of  the
Trustee, its agents and counsel.

                 If the Company  fails to pay such amounts  forthwith  upon such
demand,  the Trustee,  in its own name and as trustee of an express  trust,  may
institute  a  judicial  proceeding  for the  collection  of the  sums so due and
unpaid,  and may prosecute such proceeding to judgment or final decree,  and may
enforce the same against the Company or any other  obligor upon such  Securities
of such series and  collect the moneys  adjudged or decreed to be payable in the
manner  provided by law out of the property of the Company or any other  obligor
upon such Securities of such series, wherever situated.

                 If an Event of Default with respect to Securities of any series
occurs and is continuing,  the Trustee may in its discretion  proceed to protect
and  enforce  its  rights and the rights of the  Holders of  Securities  of such
series and any related coupons by such appropriate  judicial  proceedings as the
Trustee  shall deem most  effectual  to protect  and  

                                      -28-

enforce any such rights, whether for the specific enforcement of any covenant or
agreement  in this  Indenture  or in aid of the  exercise  of any power  granted
herein, or to enforce any other proper remedy.

                 SECTION 504.  Trustee May File Proofs of Claim.  In case of the
pendency   of   any   receivership,    insolvency,   liquidation,    bankruptcy,
reorganization,   arrangement,   adjustment,   composition   or  other  judicial
proceeding  relative to the Company or any other obligor upon the  Securities or
the  property of the Company or of such other  obligor or their  creditors,  the
Trustee  (irrespective  of whether the principal of the Securities of any series
shall  then be due  and  payable  as  therein  expressed  or by  declaration  or
otherwise and  irrespective of whether the Trustee shall have made any demand on
the  Company  for the payment of overdue  principal  of, or premium,  if any, or
interest on, the Securities) shall be entitled and empowered, by intervention in
such proceeding or otherwise:

                           (i) to file and prove a claim  for the whole  amount,
         or such lesser amount as may be provided for in the  Securities of such
         series, of principal (and premium,  if any) and interest and Additional
         Amount,  if any,  owing and unpaid in respect of the  Securities and to
         file such other papers or documents as may be necessary or advisable in
         order to have the claims of the  Trustee  (including  any claim for the
         reasonable  compensation,  expenses,  disbursements and advances of the
         Trustee,  its agents and  counsel)  and of the Holders  allowed in such
         judicial proceeding, and

                           (ii) to  collect  and  receive  any  moneys  or other
         property  payable or  deliverable  on any such claims and to distribute
         the same;

and any custodian,  receiver,  assignee, trustee,  liquidator,  sequestrator (or
other similar official) in any such judicial  proceeding is hereby authorized by
each Holder of  Securities  of such series and coupons to make such  payments to
the Trustee,  and in the event that the Trustee  shall  consent to the making of
such payments  directly to the Holders,  to pay to the Trustee any amount due to
it for the reasonable compensation,  expenses, disbursements and advances of the
Trustee and any  predecessor  Trustee,  their agents and counsel,  and any other
amounts due the Trustee or any predecessor Trustee under Section 606.

                 Nothing  herein  contained  shall be  deemed to  authorize  the
Trustee to authorize or consent to or accept or adopt on behalf of any Holder of
a Security  or coupon any plan of  reorganization,  arrangement,  adjustment  or
composition  affecting  the  Securities  or  coupons or the rights of any Holder
thereof,  or to  authorize  the  Trustee  to vote in respect of the claim of any
Holder of a Security or coupon in any such proceeding.

                 SECTION 505.  Trustee May Enforce Claims Without  Possession of
Securities or Coupons.  All rights of action and claims under this  Indenture or
any of the  Securities or coupons may be prosecuted  and enforced by the Trustee
without the  possession of any of the  Securities  or coupons or the  production
thereof in any proceeding relating thereto,  and any such proceeding  instituted
by the Trustee shall be brought in its own name as trustee of an express  trust,
and any  recovery  of judgment  shall,  after  provision  for the payment of the
reasonable  compensation,  expenses,  disbursements and advances of the Trustee,
its agents and counsel,  be for the ratable benefit of the Holders of Securities
and coupons in respect of which such judgment has been recovered.

                 SECTION  506.   Application  of  Money  Collected.   Any  money
collected  by the  Trustee  pursuant  to this  Article  shall be  applied in the
following  order,  at the date or dates fixed by the Trustee and, in case of the
distribution  of such money on  account of  principal  (or  premium,  if any) or
interest and any  Additional  Amounts,  upon  presentation  of the Securities or
coupons, or both, as the case may be, and the notation thereon of the payment if
only partially paid and upon surrender thereof if fully paid:

                           FIRST:  To  the  payment  of all  amounts  due to the
         Trustee and any predecessor Trustee under Section 606;

                           SECOND:  To the payment of the  amounts  then due and
         unpaid upon the Securities  and coupons for principal (and premium,  if
         any) and interest and any  Additional  Amounts  payable,  in respect of

                                      -29-

         which  or for the  benefit  of which  such  money  has been  collected,
         ratably,  without preference or priority of any kind,  according to the
         aggregate  amounts due and payable on such  Securities  and coupons for
         principal  (and  premium,  if any),  interest and  Additional  Amounts,
         respectively; and

                           THIRD:  To the payment of the  remainder,  if any, to
         the Company.

                 SECTION 507.  Limitation on Suits. No Holder of any Security of
any  series  or any  related  coupon  shall  have  any  right to  institute  any
proceeding,  judicial or otherwise,  with respect to this Indenture,  or for the
appointment of a receiver or trustee, or for any other remedy hereunder, unless:

                           (1) such Holder has  previously  given written notice
         to the Trustee of a  continuing  Event of Default  with  respect to the
         Securities of that series;

                           (2)  the  Holders  of not  less  than a  majority  in
         principal  amount of the  Outstanding  Securities  of that series shall
         have made written  request to the Trustee to institute  proceedings  in
         respect of such Event of Default in its own name as Trustee hereunder;

                           (3)  such  Holder  or  Holders  have  offered  to the
         Trustee   reasonable   indemnity   against  the  costs,   expenses  and
         liabilities to be incurred in compliance with such request;

                           (4) the Trustee for 60 days after its receipt of such
         notice, request and offer of indemnity has failed to institute any such
         proceeding; and

                           (5)  no  direction  inconsistent  with  such  written
         request has been given to the Trustee  during such 60-day period by the
         Holders of a majority in principal amount of the Outstanding Securities
         of that series;

it being  understood and intended that no one or more of such Holders shall have
any right in any manner  whatever by virtue of, or by availing of, any provision
of this  Indenture to affect,  disturb or  prejudice  the rights of any other of
such Holders,  or to obtain or to seek to obtain priority or preference over any
other of such  Holders or to enforce any right under this  Indenture,  except in
the manner  herein  provided  and for the equal and ratable  benefit of all such
Holders.

                 SECTION  508.   Unconditional   Right  of  Holders  to  Receive
Principal, Premium, if any, Interest and Additional Amounts. Notwithstanding any
other  provision in this  Indenture,  the Holder of any Security or coupon shall
have the right which is absolute  and  unconditional  to receive  payment of the
principal  of (and  premium,  if any)  and  (subject  to  Sections  305 and 307)
interest on, and any Additional  Amounts in respect of, such Security or payment
of such coupon on the respective due dates  expressed in such Security or coupon
(or, in the case of redemption,  on the  Redemption  Date) and to institute suit
for the  enforcement of any such payment,  and such rights shall not be impaired
without the consent of such Holder.

                 SECTION 509. Restoration of Rights and Remedies. If the Trustee
or any Holder of a Security or coupon has  instituted  any proceeding to enforce
any  right  or  remedy  under  this  Indenture  and  such  proceeding  has  been
discontinued or abandoned for any reason,  or has been  determined  adversely to
the  Trustee or to such  Holder,  then and in every such case the  Company,  the
Trustee  and the  Holders  of  Securities  and  coupons  shall,  subject  to any
determination  in such  proceeding,  be restored  severally and  respectively to
their former  positions  hereunder and thereafter all rights and remedies of the
Trustee and the Holders  shall  continue as though no such  proceeding  had been
instituted.

                 SECTION  510.  Rights  and  Remedies   Cumulative.   Except  as
otherwise  provided  with respect to the  replacement  or payment of  mutilated,
destroyed, lost or stolen Securities or coupons in the last paragraph of Section
306, no right or remedy herein  conferred  upon or reserved to the Trustee or to
the Holders of  Securities  or coupons is intended to be  exclusive of any other
right or remedy,  and every right and remedy shall,  to the extent  permitted by
law,  

                                      -30-

be cumulative and in addition to every other right and remedy given hereunder or
now or hereafter  existing at law or in equity or  otherwise.  The  assertion or
employment of any right or remedy hereunder, or otherwise, shall not prevent the
concurrent assertion or employment of any other appropriate right or remedy.

                 SECTION 511. Delay or Omission Not Waiver. No delay or omission
of the Trustee or of any Holder of any  Security or coupon to exercise any right
or remedy  accruing  upon any Event of  Default  shall  impair any such right or
remedy or  constitute  a waiver of any such Event of Default or an  acquiescence
therein.  Every right and remedy  given by this Article or by law to the Trustee
or to the Holders  may be  exercised  from time to time,  and as often as may be
deemed expedient,  by the Trustee or by the Holders of Securities or coupons, as
the case may be.

                 SECTION 512.  Control by Holders of Securities.  The Holders of
not less than a majority in principal  amount of the  Outstanding  Securities of
any  series  shall  have the  right to  direct  the  time,  method  and place of
conducting any proceeding for any remedy  available to the Trustee or exercising
any trust or power  conferred on the Trustee with respect to the  Securities  of
such series; provided that

                           (1) such direction  shall not be in conflict with any
rule of law or with this Indenture,

                           (2) the  Trustee  may take any  other  action  deemed
         proper by the Trustee which is not  inconsistent  with such  direction,
         and

                           (3) the Trustee  need not take any action which might
         expose it to personal liability or be unduly prejudicial to the Holders
         of Securities of such series not joining therein.

                 SECTION 513.  Waiver of Past Defaults.  The Holders of not less
than a majority in principal amount of the Outstanding  Securities of any series
may on  behalf of the  Holders  of all the  Securities  of such  series  and any
related coupons waive any past default hereunder with respect to such series and
its consequences, except a default

                           (1) in the payment of the  principal  of (or premium,
         if any) or interest on or Additional  Amounts payable in respect of any
         Security of such series or any related coupons, or

                           (2) in  respect  of a covenant  or  provision  hereof
         which under  Article  Nine  cannot be  modified or amended  without the
         consent  of the  Holder of each  Outstanding  Security  of such  series
         affected.

         Upon any such waiver,  such default shall cease to exist, and any Event
of  Default  arising  therefrom  shall be deemed to have been  cured,  for every
purpose of this Indenture;  but no such waiver shall extend to any subsequent or
other default or Event of Default or impair any right consequent thereon.

                 SECTION  514.  Waiver of Usury,  Stay or  Extension  Laws.  The
Company covenants (to the extent that it may lawfully do so) that it will not at
any time insist upon, or plead,  or in any manner  whatsoever  claim or take the
benefit or advantage of, any usury, stay or extension law wherever enacted,  now
or at any time  hereafter  in  force,  which may  affect  the  covenants  or the
performance  of this  Indenture;  and the  Company  (to the  extent  that it may
lawfully do so) hereby  expressly  waives all benefit or  advantage  of any such
law, and covenants that it will not hinder, delay or impede the execution of any
power herein granted to the Trustee, but will suffer and permit the execution of
every such power as though no such law had been enacted.

                 SECTION  515.  Undertaking  for  Costs.  All  parties  to  this
Indenture agree, and each Holder of any Security by his acceptance thereof shall
be deemed to have agreed,  that any court may in its discretion  require, in any
suit for the enforcement of any right or remedy under this Indenture,  or in any
suit against the Trustee for any action  taken or omitted by it as Trustee,  the
filing by any party  litigant in such suit of an undertaking to pay the costs of
such suit, and that such court may in its discretion  assess  reasonable  costs,
including  reasonable  attorneys' fees,  against any party litigant in such suit
having due regard to the merits and good faith of the claims or defenses made by
such party  litigant;  but the provisions of this Section shall not apply to any
suit instituted by the Trustee,  to any suit instituted by 

                                      -31-

any Holder,  or group of Holders,  holding in the aggregate more than a majority
in principal amount of the Outstanding Securities,  or to any suit instituted by
any Holder for the  enforcement  of the payment of the principal of (or premium,
if any) or interest on any Security on or after the respective Stated Maturities
expressed  in such  Security  (or,  in the case of  redemption,  on or after the
Redemption Date).

                                   ARTICLE SIX

                                   THE TRUSTEE

                 SECTION  601.  Notice of  Defaults.  Within  90 days  after the
occurrence  of any  default  hereunder  with  respect to the  Securities  of any
series,  the Trustee shall transmit in the manner and to the extent  provided in
TIA Section  313(c),  notice of such  default  hereunder  known to the  Trustee,
unless such default shall have been cured or waived;  provided,  however,  that,
except in the case of a default in the payment of the  principal of (or premium,
if any) or interest on or any  Additional  Amounts or sinking  fund  installment
with respect to the Securities of such series, the Trustee shall be protected in
withholding such notice if and so long as Responsible Officers of the Trustee in
good faith  determine that the  withholding of such notice is in the interest of
the Holders of the Securities and coupons of such series;  and provided  further
that in the case of any default or breach of the character  specified in Section
501(4) with respect to the Securities and coupons of such series, no such notice
to Holders shall be given until at least 60 days after the  occurrence  thereof.
For the purpose of this Section, the term "default" means any event which is, or
after  notice or lapse of time or both would  become,  an Event of Default  with
respect to the Securities of such series.

                 SECTION  602.  Certain  Rights  of  Trustee.   Subject  to  the
provisions of TIA Section 315(a) through 315(d):

                           (1) the  Trustee may rely and shall be  protected  in
         acting or  refraining  from  acting upon any  resolution,  certificate,
         statement,  instrument,  opinion,  report, notice, request,  direction,
         consent,  order,  bond,  debenture,  note,  coupon  or  other  paper or
         document  believed  by it to be  genuine  and to have  been  signed  or
         presented by the proper party or parties;

                           (2) any request or direction of the Company mentioned
         herein shall be sufficiently  evidenced by a Company Request or Company
         Order (other than delivery of any  Security,  together with any coupons
         appertaining  thereto,  to the Trustee for  authentication and delivery
         pursuant  to  Section  303 which  shall be  sufficiently  evidenced  as
         provided  therein) and any  resolution of the Board of Directors may be
         sufficiently evidenced by a Board Resolution;

                           (3) whenever in the  administration of this Indenture
         the  Trustee  shall  deem it  desirable  that a  matter  be  proved  or
         established  prior to taking,  suffering or omitting to take any action
         hereunder,  the Trustee  (unless other evidence be herein  specifically
         prescribed)  may, in the absence of bad faith on its part, rely upon an
         Officers' Certificate;

                           (4) the  Trustee  may  consult  with  counsel and the
         advice of such  counsel or any  Opinion  of  Counsel  shall be full and
         complete  authorization  and protection in respect of any action taken,
         suffered  or omitted  by it  hereunder  in good  faith and in  reliance
         thereon;

                           (5) the  Trustee  shall  be under  no  obligation  to
         exercise any of the rights or powers vested in it by this  Indenture at
         the request or  direction  of any of the Holders of  Securities  of any
         series or any related coupons  pursuant to this Indenture,  unless such
         Holders  shall  have  offered to the  Trustee  reasonable  security  or
         indemnity  against the costs,  expenses and liabilities  which might be
         incurred by it in compliance with such request or direction;

                                      -32-

                           (6) the  Trustee  shall  not be  bound  to  make  any
         investigation  into the  facts or  matters  stated  in any  resolution,
         certificate,  statement,  instrument, opinion, report, notice, request,
         direction, consent, order, bond, debenture, note, coupon or other paper
         or document, but the Trustee, in its discretion,  may make such further
         inquiry or investigation  into such facts or matters as it may see fit,
         and, if the Trustee  shall  determine to make such  further  inquiry or
         investigation,  it shall be entitled to examine the books,  records and
         premises of the Company, personally or by agent or attorney;

                           (7) the  Trustee  may  execute  any of the  trusts or
         powers  hereunder or perform any duties hereunder either directly or by
         or through agents or attorneys and the Trustee shall not be responsible
         for any  misconduct  or negligence on the part of any agent or attorney
         appointed with due care by it hereunder; and

                           (8) the  Trustee  shall not be liable  for any action
         taken,  suffered or omitted by it in good faith and reasonably believed
         by it to be  authorized  or within the  discretion  or rights or powers
         conferred upon it by this Indenture.

                 The  Trustee  shall not be  required  to expend or risk its own
funds or otherwise  incur any financial  liability in the  performance of any of
its duties hereunder, or in the exercise of any of its rights or powers.

                 SECTION  603.  Not  Responsible  for  Recitals  or  Issuance of
Securities.  The recitals  contained  herein and in the  Securities,  except the
Trustee's  certificate of  authentication,  and in any coupons shall be taken as
the  statements of the Company,  and neither the Trustee nor any  Authenticating
Agent assumes any  responsibility  for their  correctness.  The Trustee makes no
representations  as to the validity or  sufficiency  of this Indenture or of the
Securities  or  coupons,  except  that the  Trustee  represents  that it is duly
authorized to execute and deliver this  Indenture,  authenticate  the Securities
and   perform   its   obligations   hereunder.   Neither  the  Trustee  nor  the
Authenticating  Agent shall be  accountable  for the use or  application  by the
Company of Securities or the proceeds thereof.

                 SECTION  604.  May Hold  Securities.  The  Trustee,  any Paying
Agent,  Security  Registrar,  Authenticating  Agent  or any  other  agent of the
Company,  in its  individual  or any other  capacity,  may  become  the owner or
pledgee of Securities and coupons and,  subject to TIA Sections  310(b) and 311,
may  otherwise  deal with the  Company  with the same rights it would have if it
were not Trustee, Paying Agent, Security Registrar, Authenticating Agent or such
other agent.

                 SECTION 605. Money Held in Trust.  Money held by the Trustee in
trust  hereunder  need not be  segregated  from other funds except to the extent
required by law.  The Trustee  shall be under no  liability  for interest on any
money received by it hereunder except as otherwise agreed with the Company.

                 SECTION  606.  Compensation  and  Reimbursement.   The  Company
agrees:

                           (1)  to  pay  to  the  Trustee   from  time  to  time
         reasonable  compensation  for all  services  rendered  by it  hereunder
         (which  compensation  shall not be limited by any  provision  of law in
         regard to the compensation of a trustee of an express trust);

                           (2) except as otherwise expressly provided herein, to
         reimburse  each of the Trustee  and any  predecessor  Trustee  upon its
         request  for  all  reasonable  expenses,   disbursements  and  advances
         incurred or made by the Trustee in  accordance  with any  provision  of
         this Indenture (including the reasonable  compensation and the expenses
         and disbursements of its agents and counsel),  except any such expense,
         disbursement or advance as may be attributable to its negligence or bad
         faith; and

                           (3)  to  indemnify   each  of  the  Trustee  and  any
         predecessor  Trustee  for, and to hold it harmless  against,  any loss,
         liability or expense  incurred  without  negligence or bad faith on its
         own  part,  arising  out of or in  connection  with the  acceptance  or
         administration  of the trust or trusts  hereunder,  including the costs

                                      -33-

         and  expenses of  defending  itself  against any claim or  liability in
         connection  with the  exercise or  performance  of any of its powers or
         duties hereunder.

                 When  the  Trustee  incurs  expenses  or  renders  services  in
connection  with an Event of  Default  specified  in  Section  501(6) or Section
501(7),  the  expenses  (including  the  reasonable  charges and expenses of its
counsel)  and the  compensation  for the  services  are  intended to  constitute
expenses of  administration  under any applicable  Federal or state  bankruptcy,
insolvency or other similar law.

                 As  security  for the  performance  of the  obligations  of the
Company  under  this  Section,  the  Trustee  shall  have  a lien  prior  to the
Securities upon all property and funds held or collected by the Trustee as such,
except funds held in trust for the payment of principal of (or premium,  if any)
or interest on particular Securities or coupons.

                 The provisions of this Section shall survive the termination of
this Indenture.

                 SECTION   607.   Corporate   Trustee   Required;   Eligibility;
Conflicting  Interests.  There shall at all times be a Trustee  hereunder  which
shall be eligible to act as Trustee under TIA Section 310(a)(1) and shall have a
combined  capital  and  surplus  of at least  $50,000,000.  If such  corporation
publishes  reports  of  condition  at  least  annually,  pursuant  to law or the
requirements of Federal, state,  Territorial or District of Columbia supervising
or  examining  authority,  then for the purposes of this  Section,  the combined
capital  and  surplus  of such  corporation  shall be deemed to be its  combined
capital  and  surplus as set forth in its most  recent  report of  condition  so
published.  If at any time the Trustee  shall cease to be eligible in accordance
with the provisions of this Section,  it shall resign  immediately in the manner
and with the effect hereinafter specified in this Article.

                 SECTION 608. Resignation and Removal; Appointment of Successor.

                 (a) No resignation or removal of the Trustee and no appointment
of a successor Trustee pursuant to this Article shall become effective until the
acceptance  of  appointment  by the  successor  Trustee in  accordance  with the
applicable requirements of Section 609.

                 (b) The  Trustee  may  resign at any time with  respect  to the
Securities  of one or more  series  by  giving  written  notice  thereof  to the
Company.  If an instrument  of acceptance by a successor  Trustee shall not have
been  delivered to the Trustee within 30 days after the giving of such notice of
resignation,   the  resigning  Trustee  may  petition  any  court  of  competent
jurisdiction for the appointment of a successor Trustee.

                 (c) The Trustee may be removed at any time with  respect to the
Securities of any series by Act of the Holders of a majority in principal amount
of the Outstanding Securities of such series delivered to the Trustee and to the
Company.

                 (d)        If at any time:

                           (1)  the  Trustee  shall  fail  to  comply  with  the
         provisions of TIA Section 310(b) after written request  therefor by the
         Company or by any Holder of a Security  who has been a bona fide Holder
         of a Security for at least six months, or

                           (2) the  Trustee  shall  cease to be  eligible  under
         Section 607(a) and shall fail to resign after written request  therefor
         by the Company or by any Holder of a Security  who has been a bona fide
         Holder of a Security for at least six months, or

                           (3) the Trustee  shall become  incapable of acting or
         shall be adjudged a bankrupt or  insolvent or a receiver of the Trustee
         or of its property  shall be appointed or any public officer shall take
         charge or control of the Trustee or of its  property or affairs for the
         purpose of rehabilitation, conservation or liquidation,

                                      -34-

then, in any such case, (i) the Company by or pursuant to a Board Resolution may
remove  the  Trustee  and  appoint  a  successor  Trustee  with  respect  to all
Securities,  or (ii) subject to TIA Section 315(e), any Holder of a Security who
has been a bona fide Holder of a Security for at least six months may, on behalf
of himself and all others  similarly  situated,  petition any court of competent
jurisdiction  for the removal of the Trustee with respect to all  Securities and
the appointment of a successor Trustee or Trustees.

                 (e) If the Trustee shall resign, be removed or become incapable
of acting,  or if a vacancy  shall occur in the office of Trustee for any reason
with  respect  to the  Securities  of one or more  series,  the  Company,  by or
pursuant to a Board  Resolution,  shall promptly appoint a successor  Trustee or
Trustees  with  respect  to the  Securities  of that or those  series  (it being
understood that any such successor  Trustee may be appointed with respect to the
Securities of one or more or all of such series and that at any time there shall
be only one Trustee with respect to the  Securities of any  particular  series).
If,  within one year after such  resignation,  removal or  incapability,  or the
occurrence of such vacancy,  a successor  Trustee with respect to the Securities
of any  series  shall  be  appointed  by Act of the  Holders  of a  majority  in
principal  amount of the Outstanding  Securities of such series delivered to the
Company and the retiring  Trustee,  the  successor  Trustee so appointed  shall,
forthwith upon its acceptance of such appointment,  become the successor Trustee
with respect to the  Securities of such series and to that extent  supersede the
successor Trustee appointed by the Company. If no successor Trustee with respect
to the  Securities  of any series shall have been so appointed by the Company or
the Holders of Securities  and accepted  appointment  in the manner  hereinafter
provided  any Holder of a Security who has been a bona fide Holder of a Security
of such  series for at least six months may, on behalf of himself and all others
similarly  situated,  petition  any  court  of  competent  jurisdiction  for the
appointment of a successor Trustee with respect to Securities of such series.

                 (f) The Company shall give notice of each  resignation and each
removal of the Trustee  with  respect to the  Securities  of any series and each
appointment of a successor  Trustee with respect to the Securities of any series
in the manner  provided for notices to the Holders of Securities in Section 106.
Each notice shall include the name of the successor  Trustee with respect to the
Securities of such series and the address of its Corporate Trust Office.

                 SECTION 609.  Acceptance of Appointment by Successor.

                  (a)  In  case  of the  appointment  hereunder  of a  successor
Trustee with  respect to all  Securities,  every such  successor  Trustee  shall
execute,  acknowledge and deliver to the Company and to the retiring  Trustee an
instrument accepting such appointment,  and thereupon the resignation or removal
of the retiring  Trustee  shall become  effective  and such  successor  Trustee,
without any further act,  deed or  conveyance,  shall become vested with all the
rights,  powers, trusts and duties of the retiring Trustee; but, upon request of
the Company or the successor Trustee,  such retiring Trustee shall, upon payment
of its charges, execute and deliver an instrument transferring to such successor
Trustee all the rights,  powers and trusts of the  retiring  Trustee,  and shall
duly  assign,  transfer and deliver to such  successor  Trustee all property and
money held by such  retiring  Trustee  hereunder,  subject  nevertheless  to its
claim, if any, provided for in Section 606.

                 (b) In case of the appointment hereunder of a successor Trustee
with respect to the Securities of one or more (but not all) series, the Company,
the retiring  Trustee and each successor  Trustee with respect to the Securities
of one or more  series  shall  execute  and  deliver an  indenture  supplemental
hereto,  pursuant to Article Nine hereof,  wherein each successor  Trustee shall
accept such  appointment and which (1) shall contain such provisions as shall be
necessary  or  desirable  to  transfer  and  confirm  to,  and to vest in,  each
successor  Trustee all the  rights,  powers,  trusts and duties of the  retiring
Trustee  with  respect to the  Securities  of that or those  series to which the
appointment of such successor  Trustee  relates,  (2) if the retiring Trustee is
not retiring with respect to all  Securities,  shall contain such  provisions as
shall be deemed  necessary or desirable to confirm that all the rights,  powers,
trusts and duties of the retiring Trustee with respect to the Securities of that
or those series as to which the retiring  Trustee is not retiring shall continue
to be vested in the retiring Trustee,  and (3) shall add to or change any of the
provisions of this  Indenture as shall be necessary to provide for or facilitate
the  administration  of the trusts hereunder by more than one Trustee,  it being
understood  that  nothing  herein  or  in  such  supplemental   indenture  shall
constitute  such  Trustees  co-trustees  of the same  trust  and that  each such
Trustee shall be trustee of a trust or trusts hereunder  separate and apart from
any trust or 

                                      -35-

trusts hereunder  administered by any other such Trustee; and upon the execution
and delivery of such  supplemental  indenture the  resignation or removal of the
retiring  Trustee shall become effective to the extent provided therein and each
such  successor  Trustee,  without any further act,  deed or  conveyance,  shall
become  vested with all the rights,  powers,  trusts and duties of the  retiring
Trustee  with  respect to the  Securities  of that or those  series to which the
appointment of such successor Trustee relates; but, on request of the Company or
any successor  Trustee,  such retiring  Trustee shall duly assign,  transfer and
deliver to such  successor  Trustee all property and money held by such retiring
Trustee  hereunder  with  respect to the  Securities  of that or those series to
which the appointment of such successor Trustee relates.

                 (c) Upon  request of any such  successor  Trustee,  the Company
shall execute any and all instruments  for more fully and certainly  vesting in,
and  confirming  to such  successor  Trustee all such rights,  powers and trusts
referred to in paragraph (a) or (b) of this Section, as the case may be.

                 (d) No successor Trustee shall accept its appointment unless at
the time of such  acceptance  such  successor  Trustee  shall be  qualified  and
eligible under this Article.

                 SECTION 610. Merger, Conversion, Consolidation or Succession to
Business.  Any corporation  into which the Trustee may be merged or converted or
with which it may be consolidated, or any corporation resulting from any merger,
conversion  or  consolidation  to which  the  Trustee  shall be a party,  or any
corporation  succeeding  to all or  substantially  all  of the  corporate  trust
business  of the  Trustee,  shall be the  successor  of the  Trustee  hereunder;
provided such corporation  shall be otherwise  qualified and eligible under this
Article,  without the execution or filing of any paper or any further act on the
part of any of the parties hereto.  In case any Securities or coupons shall have
been  authenticated,  but not  delivered,  by the  Trustee  then in office,  any
successor by merger,  conversion or consolidation to such authenticating Trustee
may  adopt  such  authentication  and  deliver  the  Securities  or  coupons  so
authenticated  with the same  effect as if such  successor  Trustee  had  itself
authenticated  such  Securities  or coupons.  In case any  Securities or coupons
shall  not  have  been  authenticated  by such  predecessor  Trustee,  any  such
successor  Trustee may authenticate  and deliver such Securities or coupons,  in
either its own name or that of its predecessor Trustee,  with the full force and
effect which this Indenture  provides for the certificate of  authentication  of
the Trustee.

                 SECTION 611.  Appointment of Authentication  Agent. At any time
when any of the  Securities  remain  Outstanding,  the  Trustee  may  appoint an
Authenticating  Agent or Agents with respect to one or more series of Securities
which  shall be  authorized  to act on behalf  of the  Trustee  to  authenticate
Securities  of such series  issued upon  exchange,  registration  of transfer or
partial redemption or repayment thereof,  and Securities so authenticated  shall
be entitled to the benefits of this  Indenture and shall be valid and obligatory
for  all  purposes  as if  authenticated  by the  Trustee  hereunder.  Any  such
appointment  shall  be  evidenced  by  an  instrument  in  writing  signed  by a
Responsible Officer of the Trustee, a copy of which instrument shall be promptly
furnished to the Company.  Wherever  reference is made in this  Indenture to the
authentication  and  delivery  of  Securities  by the  Trustee or the  Trustee's
certificate  of  authentication,  such  reference  shall be  deemed  to  include
authentication and delivery on behalf of the Trustee by an Authenticating  Agent
and a  certificate  of  authentication  executed  on behalf of the Trustee by an
Authenticating  Agent.  Each  Authenticating  Agent shall be  acceptable  to the
Company and, except as may otherwise be provided  pursuant to Section 301, shall
at all  times be a bank or trust  company  or  corporation  organized  and doing
business and in good standing  under the laws of the United States of America or
of any State or the District of Columbia,  authorized  under such laws to act as
Authenticating  Agent,  having a combined  capital  and surplus of not less than
$50,000,000  and  subject  to  supervision  or  examination  by federal or state
authorities.  If such  Authenticating  Agent  publishes  reports of condition at
least annually, pursuant to law or the requirements of the aforesaid supervising
or  examining  authority,  then for the purposes of this  Section,  the combined
capital  and  surplus  of such  Authenticating  Agent  shall be deemed to be its
combined capital and surplus as set forth in its most recent report of condition
so  published.  In case at any time an  Authenticating  Agent  shall cease to be
eligible in accordance with the provisions of this Section,  such Authenticating
Agent shall resign  immediately  in the manner and with the effect  specified in
this Section.

                 Any  corporation  into  which an  Authenticating  Agent  may be
merged or converted  or with which it may be  consolidated,  or any  corporation
resulting  from  any  merger,   conversion  or   consolidation   to  which  such

                                      -36-

Authenticating  Agent shall be a party,  or any  corporation  succeeding  to the
corporate agency or corporate trust business of an Authenticating  Agent,  shall
continue to be an  Authenticating  Agent,  provided  such  corporation  shall be
otherwise  eligible  under this Section,  without the execution or filing of any
paper or further act on the part of the Trustee or the Authenticating Agent.

                 An Authenticating Agent for any series of Securities may at any
time  resign by giving  written  notice of  resignation  to the Trustee for such
series and to the Company.  The Trustee for any series of Securities  may at any
time terminate the agency of an Authenticating Agent by giving written notice of
termination to such Authenticating Agent and to the Company. Upon receiving such
a notice of resignation or upon such a termination,  or in case at any time such
Authenticating  Agent  shall  cease  to  be  eligible  in  accordance  with  the
provisions of this Section,  the Trustee for such series may appoint a successor
Authenticating  Agent  which shall be  acceptable  to the Company and shall give
notice of such  appointment  to all  Holders of  Securities  of the series  with
respect to which such Authenticating Agent will serve in the manner set forth in
Section  106.  Any  successor   Authenticating  Agent  upon  acceptance  of  its
appointment hereunder shall become vested with all the rights, powers and duties
of its  predecessor  hereunder,  with like effect as if  originally  named as an
Authenticating  Agent  herein.  No  successor   Authenticating  Agent  shall  be
appointed unless eligible under the provisions of this Section.

                 The  Company  agrees to pay to each  Authenticating  Agent from
time to time reasonable  compensation including  reimbursement of its reasonable
expenses for its services under this Section.

                 If an  appointment  with  respect to one or more series is made
pursuant  to this  Section,  the  Securities  of such  series may have  endorsed
thereon,   in  addition  to  or  in  lieu  of  the  Trustee's   certificate   of
authentication,  an alternate certificate of authentication substantially in the
following form:

                                    This is one of the  Securities of the series
                 designated   therein   referred  to  in  the   within-mentioned
                 Indenture.

                           ____________________________________
                                                     as Trustee


                           By:_________________________________
                                        as Authenticating Agent


                           By:_________________________________
                                             Authorized Officer


                                  ARTICLE SEVEN

                HOLDERS' LISTS AND REPORTS BY TRUSTEE AND COMPANY

                 SECTION  701.  Disclosure  of Names and  Addresses  of Holders.
Every Holder of Securities or coupons, by receiving and holding the same, agrees
with the Company and the  Trustee  that  neither the Company nor the Trustee nor
any  Authenticating  Agent nor any Paying Agent nor any Security Registrar shall
be held  accountable  by reason of the  disclosure of any  information as to the
names and addresses of the Holders of Securities in accordance  with TIA Section
312, regardless of the source from which such information was derived,  and that
the Trustee  shall not be held  accountable  by reason of mailing  any  material
pursuant to a request made under TIA Section 312(b).

                 SECTION 702. Reports by Trustee. Within 60 days after May 15 of
each  year  commencing  with  the  first  May 15 after  the  first  issuance  of
Securities pursuant to this Indenture, the Trustee shall transmit by mail to all

                                      -37-

Holders of Securities as provided in TIA Section  313(c) a brief report dated as
of such May 15 if required by TIA Section 313(a).

                 SECTION 703.  Reports by Company.  The Company will:

                           (1) file with the  Trustee,  within 15 days after the
         Company is required to file the same with the Commission, copies of the
         annual reports and of the information,  documents and other reports (or
         copies of such portions of any of the foregoing as the  Commission  may
         from time to time by rules and regulations prescribe) which the Company
         may be required to file with the  Commission  pursuant to Section 13 or
         Section  15(d)  of the  Securities  Exchange  Act of 1934;  or,  if the
         Company  is not  required  to file  information,  documents  or reports
         pursuant to either of such Sections, then it will file with the Trustee
         and the Commission, in accordance with rules and regulations prescribed
         from  time to time by the  Commission,  such of the  supplementary  and
         periodic  information,  documents  and  reports  which may be  required
         pursuant  to  Section  13 of the  Securities  Exchange  Act of  1934 in
         respect of a security  listed and  registered on a national  securities
         exchange  as may be  prescribed  from  time to time in such  rules  and
         regulations;

                           (2) file  with the  Trustee  and the  Commission,  in
         accordance with rules and  regulations  prescribed from time to time by
         the Commission, such additional information, documents and reports with
         respect to compliance by the Company with the  conditions and covenants
         of this  Indenture  as may be required  from time to time by such rules
         and regulations; and

                           (3)  transmit by mail to the  Holders of  Securities,
         within 30 days after the filing thereof with the Trustee, in the manner
         and to the extent provided in TIA Section 313(c), such summaries of any
         information,  documents and reports required to be filed by the Company
         pursuant to  paragraphs  (1) and (2) of this section as may be required
         by  rules  and  regulations   prescribed  from  time  to  time  by  the
         Commission.

                 SECTION 704.  Company to Furnish to Trustee Names and Addresses
of Holders. The Company will furnish or cause to be furnished to the Trustee:

                 (a)  semi-annually,  not later than 25 days  after the  Regular
Record Date for interest for each series of Securities,  a list, in such form as
the Trustee may reasonably require, of the names and addresses of the Holders of
Registered Securities of such series as of such Regular Record Date, or if there
is  no  Regular  Record  Date  for  interest  for  such  series  of  Securities,
semiannually,  upon  such  dates as are set  forth in the  Board  Resolution  or
indenture supplemental hereto authorizing such series, and

                 (b) at such other  times as the Trustee may request in writing,
within 30 days after the receipt by the Company of any such  request,  a list of
similar  form and  content  as of a date not more than 15 days prior to the time
such list is furnished;

provided,  however,  that, so long as the Trustee is the Security Registrar,  no
such list shall be required to be furnished.

                                      -38-

                                  ARTICLE EIGHT

                    MERGER, CONSOLIDATION, AND SALE OF ASSETS

                 SECTION 801. Mergers and  Consolidations of Company and Sale of
Assets.  The Company shall not consolidate or merge with or into (whether or not
the Company is the surviving  corporation),  or sell, assign,  transfer,  lease,
convey or otherwise  dispose of all or  substantially  all of its  properties or
assets in one or more related  transactions,  to another  Person  unless (a) the
Company is the  surviving  corporation  or the entity or the Person formed by or
surviving  any such  consolidation  or merger (if other than the  Company) or to
which such sale, assignment,  transfer,  lease,  conveyance or other disposition
shall have been made is a  corporation  organized or existing  under the laws of
the United States, any state thereof or the District of Columbia; (b) the Person
formed by or  surviving  any such  consolidation  or merger  (if other  than the
Company)  or the  Person  to  which  such  sale,  assignment,  transfer,  lease,
conveyance or other disposition shall have been made assumes all the obligations
of  the  Company  under  the  Securities  and  this  Indenture  (pursuant  to  a
supplemental  indenture  complying  with  Article  Nine  hereof  and  in a  form
reasonably  satisfactory  to  the  Trustee);  and  (c)  immediately  after  such
transaction no Event of Default,  and no event which,  after notice or the lapse
of time, or both, would become an Event of Default, exists.

                 SECTION  802.  Rights and Duties of Successor  Corporation.  In
case of any such consolidation,  merger,  sale, lease or conveyance and upon any
such assumption by the successor  corporation,  such successor corporation shall
succeed to and be substituted for the Company, with the same effect as if it had
been  named  herein  as the  party  of  the  first  part,  and  the  predecessor
corporation,  except in the event of a lease,  shall be  relieved of any further
obligation under this Indenture and the Securities.  Such successor  corporation
thereupon may cause to be signed, and may issue either in its own name or in the
name of the  Company,  any or all of the  Securities  issuable  hereunder  which
theretofore  shall not have been  signed by the  Company  and  delivered  to the
Trustee;  and,  upon the order of such  successor  corporation,  instead  of the
Company,  and  subject  to all the terms,  conditions  and  limitations  in this
Indenture  prescribed,  the Trustee  shall  authenticate  and shall  deliver any
Securities which previously shall have been signed and delivered by the officers
of the Company to the Trustee for authentication,  and any Securities which such
successor  corporation  thereafter shall cause to be signed and delivered to the
Trustee for that  purpose.  All the  Securities  so issued shall in all respects
have the same legal rank and  benefit  under this  Indenture  as the  Securities
theretofore or thereafter  issued in accordance with the terms of this Indenture
as though all of such  Securities  had been issued at the date of the  execution
hereof.

                 In case of any  such  consolidation,  merger,  sale,  lease  or
conveyance,  such changes in phraseology  and form (but not in substance) may be
made in the Securities thereafter to be issued as may be appropriate.


                                  ARTICLE NINE

                             SUPPLEMENTAL INDENTURES

                 SECTION  901.   Supplemental   Indentures  Without  Consent  of
Holders.  Without  the  consent of any Holders of  Securities  or  coupons,  the
Company, when authorized by or pursuant to a Board Resolution,  and the Trustee,
at any  time  and  from  time to time,  may  enter  into one or more  indentures
supplemental  hereto,  in  form  satisfactory  to the  Trustee,  for  any of the
following purposes:

                           (1) to evidence the  succession of another  Person to
         the Company and the  assumption by any such  successor of the covenants
         of the Company herein and in the Securities contained; or

                           (2) to add to the  covenants  of the  Company for the
         benefit of the Holders of all or any series of Securities  (and if such
         covenants  are to be for  the  benefit  of  less  than  all  series  of
         Securities,  stating that such  covenants are expressly  being included
         solely for the  benefit of such  series) or to  surrender  any right or
         power herein conferred upon the Company; or

                                      -39-

                           (3) to add any  additional  Events of Default for the
         benefit of the Holders of all or any series of Securities  (and if such
         Events of Default  are to be for the benefit of less than all series of
         Securities,  stating  that such Events of Default are  expressly  being
         included  solely for the benefit of such  series);  provided,  however,
         that  in  respect  of  any  such  additional  Events  of  Default  such
         supplemental  indenture  may provide for a  particular  period of grace
         after default  (which period may be shorter or longer than that allowed
         in the  case  of  other  defaults)  or  may  provide  for an  immediate
         enforcement  upon such default or may limit the  remedies  available to
         the Trustee  upon such default or may limit the right of the Holders of
         a majority in  aggregate  principal  amount of that or those  series of
         Securities  to which such  additional  Events of Default apply to waive
         such default; or

                           (4) to add to or change any of the provisions of this
         Indenture to provide that Bearer  Securities  may be  registrable as to
         principal,  to change or eliminate any  restrictions  on the payment of
         principal of or any premium or interest on Bearer Securities, to permit
         Bearer  Securities to be issued in exchange for Registered  Securities,
         to  permit  Bearer  Securities  to be  issued in  exchange  for  Bearer
         Securities of other authorized denominations or to permit or facilitate
         the issuance of Securities in uncertificated form;  provided,  that any
         such action shall not adversely  affect the interests of the Holders of
         Securities  of  any  series  or any  related  coupons  in any  material
         respect; or

                           (5) to change or eliminate  any of the  provisions of
         this  Indenture;  provided  that any such change or  elimination  shall
         become  effective  only when there is no  Security  Outstanding  of any
         series  created prior to the execution of such  supplemental  indenture
         which is entitled to the benefit of such provision; or

                           (6)      to secure the Securities; or

                           (7) to establish  the form or terms of  Securities of
         any series and any related  coupons as  permitted  by Sections  201 and
         301,  including the provisions  and  procedures  relating to Securities
         convertible into Common Shares or Preferred  Shares of the Company,  as
         the case may be; or

                           (8) to evidence  and provide  for the  acceptance  of
         appointment  hereunder  by a  successor  Trustee  with  respect  to the
         Securities  of one or more  series  and to add to or change  any of the
         provisions  of this  Indenture  as shall be necessary to provide for or
         facilitate the  administration of the trusts hereunder by more than one
         Trustee; or

                           (9) to cure any  ambiguity,  to correct or supplement
         any provision  herein which may be defective or  inconsistent  with any
         other provision herein, or to make any other provisions with respect to
         matters or questions  arising under this  Indenture  which shall not be
         inconsistent  with the  provisions  of this  Indenture;  provided  such
         provisions  shall not adversely  affect the interests of the Holders of
         Securities  of  any  series  or any  related  coupons  in any  material
         respect; or

                           (10)  to  supplement  any of the  provisions  of this
         Indenture to such extent as shall be necessary to permit or  facilitate
         the  defeasance  and discharge of any series of Securities  pursuant to
         Sections  401,  1402 and 1403;  provided that any such action shall not
         adversely  affect the  interests of the Holders of  Securities  of such
         series and any related coupons or any other series of Securities in any
         material respect.

                 SECTION 902.  Supplemental  Indentures with Consent of Holders.
With the consent of the Holders of not less than a majority in principal  amount
of all Outstanding Securities affected by such supplemental indenture, by Act of
said  Holders  delivered  to the  Company and the  Trustee,  the  Company,  when
authorized by or pursuant to a Board Resolution,  and the Trustee may enter into
an indenture  or  indentures  supplemental  hereto for the purpose of adding any
provisions to or changing in any manner or eliminating  any of the provisions of
this  Indenture  or of  modifying  in any manner  the  rights of the  Holders of
Securities and any related coupons under this Indenture; provided, 

                                      -40-

however,  that no such supplemental  indenture shall, without the consent of the
Holder of each Outstanding Security affected thereby:

                           (1) change the Stated  Maturity of the  principal  of
         (or premium, if any, on) or any installment of principal of or interest
         on, any Security; or reduce the principal amount thereof or the rate or
         amount of interest thereon or any Additional Amounts payable in respect
         thereof,  or any premium payable upon the redemption thereof, or change
         any  obligation of the Company to pay  Additional  Amounts  pursuant to
         Section 1007 (except as contemplated by Section 801(i) and permitted by
         Section  901(1)),  or reduce the amount of the principal of an Original
         Issue  Discount   Security  that  would  be  due  and  payable  upon  a
         declaration of acceleration of the Maturity thereof pursuant to Section
         502 or the amount  thereof  provable in bankruptcy  pursuant to Section
         504, or  adversely  affect any right of  repayment at the option of the
         Holder of any Security,  or change any Place of Payment  where,  or the
         currency or currencies, currency unit or units or composite currency or
         currencies  in which,  any  Security  or any  premium  or the  interest
         thereon  is  payable,  or impair  the right to  institute  suit for the
         enforcement of any such payment on or after the Stated Maturity thereof
         (or,  in the case of  redemption  or  repayment  at the  option  of the
         Holder,  on or after the Redemption  Date or the Repayment Date, as the
         case may be), or

                           (2) reduce the percentage in principal  amount of the
         Outstanding  Securities of any series,  the consent of whose Holders is
         required for any such supplemental  indenture,  or the consent of whose
         Holders is  required  for any waiver  with  respect to such  series (or
         compliance  with  certain  provisions  of  this  Indenture  or  certain
         defaults  hereunder  and  their  consequences)  provided  for  in  this
         Indenture,  or reduce the  requirements  of Section  1504 for quorum or
         voting, or

                           (3) modify  any of the  provisions  of this  Section,
         Section 513 or Section 1008, except to increase the required percentage
         to effect such action or to provide that certain  other  provisions  of
         this Indenture  cannot be modified or waived without the consent of the
         Holder of each Outstanding Security affected thereby.

                 It shall not be  necessary  for any Act of  Holders  under this
Section to approve the particular form of any proposed  supplemental  indenture,
but it shall be sufficient if such Act shall approve the substance thereof.

                 A  supplemental  indenture  which  changes  or  eliminates  any
covenant or other  provision of this Indenture which has expressly been included
solely for the benefit of one or more particular series of Securities,  or which
modifies the rights of the Holders of  Securities of such series with respect to
such covenant or other provision, shall be deemed not to affect the rights under
this Indenture of the Holders of Securities of any other series.

                 SECTION  903.   Execution  of   Supplemental   Indentures.   In
executing,  or accepting  the  additional  trusts  created by, any  supplemental
indenture  permitted by this Article or the  modification  thereby of the trusts
created by this Indenture,  the Trustee shall be entitled to receive,  and shall
be fully  protected  in relying  upon,  an Opinion of Counsel  stating  that the
execution  of such  supplemental  indenture is  authorized  or permitted by this
Indenture.  The Trustee may, but shall not be obligated  to, enter into any such
supplemental  indenture  which  affects  the  Trustee's  own  rights,  duties or
immunities under this Indenture or otherwise.

                 SECTION  904.  Effect  of  Supplemental  Indentures.  Upon  the
execution of any supplemental indenture under this Article, this Indenture shall
be modified in accordance therewith and such supplemental indenture shall form a
part  of this  Indenture  for all  purposes;  and  every  Holder  of  Securities
theretofore  or  thereafter  authenticated  and  delivered  hereunder and of any
coupon appertaining thereto shall be bound thereby.

                 SECTION  905.   Conformity  with  Trust  Indenture  Act.  Every
supplemental  indenture  executed  pursuant to this Article shall conform to the
requirements of the Trust Indenture Act as then in effect.

                                      -41-

                 SECTION  906.   Reference   in   Securities   to   Supplemental
Indentures.  Securities  of any series  authenticated  and  delivered  after the
execution of any supplemental indenture pursuant to this Article may, and shall,
if required by the Trustee,  bear a notation in form  approved by the Trustee as
to any matter provided for in such supplemental  indenture. If the Company shall
so determine,  new  Securities  of any series so modified as to conform,  in the
opinion of the Trustee and the Company,  to any such supplemental  indenture may
be prepared and executed by the Company and  authenticated  and delivered by the
Trustee in exchange for Outstanding Securities of such series.

                                   ARTICLE TEN

                                    COVENANTS

                 SECTION 1001. Payment of Principal,  Premium,  if any, Interest
and Additional Amounts.  The Company covenants and agrees for the benefit of the
Holders of each series of Securities  that it will duly and  punctually  pay the
principal of (and premium,  if any) and interest on and any  Additional  Amounts
payable in respect of the Securities of that series in accordance with the terms
of such  series  of  Securities,  any  coupons  appertaining  thereto  and  this
Indenture.  Unless  otherwise  specified  as  contemplated  by Section  301 with
respect to any series of  Securities,  any  interest  due on and any  Additional
Amounts  payable in respect of Bearer  Securities on or before  Maturity,  other
than Additional  Amounts, if any, payable as provided in Section 1007 in respect
of principal of (or premium, if any, on) such a Security,  shall be payable only
upon  presentation  and  surrender  of the  several  coupons  for such  interest
installments as are evidenced thereby as they severally mature. Unless otherwise
specified  with respect to Securities of any series  pursuant to Section 301, at
the option of the Company, all payments of principal may be paid by check to the
registered  Holder of the Registered  Security or other person entitled  thereto
against surrender of such Security.

                 SECTION 1002. Maintenance of Office or Agency. If Securities of
a series are issuable only as Registered Securities,  the Company shall maintain
in each Place of Payment for any series of  Securities an office or agency where
Securities  of that  series  may be  presented  or  surrendered  for  payment or
conversion,  where Securities of that series may be surrendered for registration
of transfer or exchange, and where notices and demands to or upon the Company in
respect of the  Securities of that series and this  Indenture may be served.  If
Securities  of a series are  issuable as Bearer  Securities,  the  Company  will
maintain:  (A) in the Borough of  Manhattan,  The City of New York, an office or
agency  where any  Registered  Securities  of that  series may be  presented  or
surrendered for payment or conversion,  where any Registered  Securities of that
series may be surrendered for registration of transfer, where Securities of that
series may be surrendered for exchange, where notices and demands to or upon the
Company in respect of the  Securities  of that series and this  Indenture may be
served and where  Bearer  Securities  of that series and related  coupons may be
presented  or  surrendered  for  payment  or  conversion  in  the  circumstances
described in the following  paragraph  (and not  otherwise);  (B) subject to any
laws or regulations  applicable  thereto,  in a Place of Payment for that series
which is located outside the United States, an office or agency where Securities
of that series and related  coupons may be presented and surrendered for payment
(including  payment of any  Additional  Amounts  payable on  Securities  of that
series pursuant to Section 1007) or conversion;  provided,  however, that if the
Securities  of that series are listed on the  Luxembourg  Stock  Exchange or any
other stock exchange  located  outside the United States and such stock exchange
shall so require, the Company will maintain a Paying Agent for the Securities of
that series in Luxembourg or any other required city located  outside the United
States,  as the case may be, so long as the Securities of that series are listed
on such exchange; and (C) subject to any laws or regulations applicable thereto,
in a Place of Payment  for that  series  located  outside  the United  States an
office  or  agency  where  any  Registered  Securities  of  that  series  may be
surrendered for registration of transfer, where Securities of that series may be
surrendered for exchange and where notices and demands to or upon the Company in
respect of the Securities of that series and this  Indenture may be served.  The
Company will give prompt written notice to the Trustee of the location,  and any
change in the  location,  of each  such  office  or  agency.  If at any time the
Company shall fail to maintain any such required  office or agency or shall fail
to furnish the Trustee with the address thereof, such presentations, surrenders,
notices and demands may be made or served at the  Corporate  Trust Office of the
Trustee,  except that Bearer  Securities of that series and the related  coupons
may  be  presented  and  surrendered  for  payment  (including  payment  of  any
Additional  Amounts  payable on Bearer  Securities  of that  series  pursuant to
Section 1007) or conversion at the offices  specified in the Security in London,
England,  and the Company hereby  appoints the same as its agent to receive such
respective  presentations,  surrenders,  notices  and  demands,  and the Company

                                      -42-

hereby  appoints  the  Trustee  its  agent to  receive  all such  presentations,
surrenders, notices and demands.

                 Unless  otherwise  specified  with  respect  to any  Securities
pursuant  to Section  301,  no payment of  principal,  premium or interest on or
Additional  Amounts in respect of Bearer  Securities shall be made at any office
or agency of the Company in the United  States or by check mailed to any address
in the United States or by transfer to an account maintained with a bank located
in the United States; provided, however, that, if the Securities of a series are
payable in Dollars,  payment of principal of and any premium and interest on any
Bearer Security  (including any Additional Amounts payable on Securities of such
series  pursuant to Section  1007) shall be made at the office of the  Company's
Paying  Agent in the City of Boston,  if (but only if) payment in Dollars of the
full amount of such principal,  premium,  interest or Additional Amounts, as the
case may be, at all offices or agencies outside the United States maintained for
such purpose by the Company in  accordance  with this  Indenture,  is illegal or
effectively precluded by exchange controls or other similar restrictions.

                 The Company may from time to time  designate  one or more other
offices or agencies  where the Securities of one or more series may be presented
or  surrendered  for any or all of such  purposes,  and  may  from  time to time
rescind  such  designation;  provided,  however,  that  no such  designation  or
rescission shall in any manner relieve the Company of its obligation to maintain
an office or agency in  accordance  with the  requirements  set forth  above for
Securities of any series for such purposes. The Company will give prompt written
notice to the Trustee of any such designation or rescission and of any change in
the location of any such other office or agency. Unless otherwise specified with
respect to any  Securities  pursuant to Section 301 with  respect to a series of
Securities,  the Company hereby designates as a Place of Payment for each series
of  Securities  the office or agency of the  Company in the City of Boston,  and
initially  appoints the Trustee at its Corporate Trust Office as Paying Agent in
such  city and as its  agent to  receive  all  such  presentations,  surrenders,
notices and demands.

                 Unless  otherwise  specified  with  respect  to any  Securities
pursuant to Section 302, if and so long as the  Securities of any series (i) are
denominated in a Foreign  Currency or (ii) may be payable in a Foreign  Currency
or so long as it is required under any other provision of this  Indenture,  then
the Company will maintain with respect to each such series of Securities,  or as
so required, at least one exchange rate agent.

                 SECTION  1003.  Money  for  Securities  Payments  to Be Held in
Trust. If the Company shall at any time act as its own Paying Agent with respect
to any series of any  Securities and any related  coupons,  it will, by no later
than 11:00 am (Boston  time) on each due date of the  principal of (and premium,
if any),  or  interest  on or  Additional  Amounts  in  respect  of,  any of the
Securities  of that series,  segregate  and hold in trust for the benefit of the
Persons entitled  thereto a sum in the currency or currencies,  currency unit or
units or composite currency or currencies in which the Securities of such series
are  payable  (except as  otherwise  specified  pursuant  to Section 301 for the
Securities of such series) sufficient to pay the principal (and premium, if any)
or interest or Additional  Amounts so becoming due until such sums shall be paid
to such Persons or otherwise  disposed of as herein provided,  and will promptly
notify the Trustee of its action or failure so to act.

                 Whenever the Company  shall have one or more Paying  Agents for
any series of Securities and any related coupons, it will, on or before each due
date of the  principal of (and  premium,  if any),  or interest on or Additional
Amounts in respect of, any  Securities  of that  series,  deposit  with a Paying
Agent a sum (in the currency or currencies,  currency unit or units or composite
currency or currencies described in the preceding  paragraph)  sufficient to pay
the  principal  (and  premium,  if any) or interest or  Additional  Amounts,  so
becoming  due,  such  sum to be held in trust  for the  benefit  of the  Persons
entitled  to such  principal,  premium or  interest  or  Additional  Amounts and
(unless such Paying Agent is the Trustee) the Company will  promptly  notify the
Trustee of its action or failure so to act.

                 The Company will cause each Paying Agent other than the Trustee
to execute and deliver to the Trustee an  instrument  in which such Paying Agent
shall agree with the Trustee,  subject to the  provisions of this Section,  that
such Paying Agent will

                                      -43-

                           (1)  hold  all  sums  held by it for the  payment  of
         principal of (and  premium,  if any) or interest on Securities in trust
         for the benefit of the Persons  entitled  thereto until such sums shall
         be paid to such Persons or otherwise disposed of as herein provided;

                           (2) give the  Trustee  notice of any  default  by the
         Company (or any other obligor upon the Securities) in the making of any
         such payment of principal (and premium, if any) or interest; and

                           (3) at any time  during the  continuance  of any such
         default, upon the written request of the Trustee,  forthwith pay to the
         Trustee all sums so held in trust by such Paying Agent.

                 The Company may at any time,  for the purpose of obtaining  the
satisfaction  and discharge of this Indenture or for any other purpose,  pay, or
by Company Order direct any Paying Agent to pay, to the Trustee all sums held in
trust by the Company or such Paying  Agent,  such sums to be held by the Trustee
upon the same  trusts as those upon which such sums were held by the  Company or
such Paying  Agent;  and,  upon such payment by any Paying Agent to the Trustee,
such Paying Agent shall be released from all further  liability  with respect to
such sums.

                 Except as otherwise  provided in the  Securities of any series,
any money  deposited  with the Trustee or any Paying Agent,  or then held by the
Company,  in trust for the payment of the principal of (and premium,  if any) or
interest on, or any Additional Amounts in respect of, any Security of any series
and remaining  unclaimed  for two years after such  principal  (and premium,  if
any), interest or Additional Amounts has become due and payable shall be paid to
the  Company  upon  Company  Request or (if then held by the  Company)  shall be
discharged from such trust; and the Holder of such Security shall thereafter, as
an  unsecured  general  creditor,  look only to the  Company for payment of such
principal of (and premium,  if any) or interest on, or any Additional Amounts in
respect of, such Security,  without interest  thereon,  and all liability of the
Trustee or such Paying Agent with respect to such trust money, and all liability
of the Company as trustee  thereof,  shall thereupon cease;  provided,  however,
that the Trustee or such Paying  Agent,  before being  required to make any such
repayment,  may at the expense of the Company cause to be published  once, in an
Authorized Newspaper, notice that such money remains unclaimed and that, after a
date  specified  therein,  which shall not be less than 30 days from the date of
such  publication,  any unclaimed  balance of such money then  remaining will be
repaid to the Company.

                 SECTION 1004. Existence.  Subject to Article Eight, the Company
will do or cause to be done all things  necessary  to preserve  and keep in full
force  and  effect  its  existence,   rights  (declaration  and  statutory)  and
franchises;  provided,  however,  that the  Company  shall  not be  required  to
preserve  any  right  or  franchise  if  the  Board  shall  determine  that  the
preservation  thereof is no longer  desirable  in the conduct of the business of
the Company.

                 SECTION 1005.  Provision of Financial  Information.  Whether or
not  required  by the rules and  regulations  of the SEC,  so long as any of the
Securities  are  outstanding,  the Company  will  furnish to the Holders (i) all
quarterly  and  annual  financial  information  that  would  be  required  to be
contained  in a filing with the SEC on Forms 10-Q and 10-K if the  Company  were
required to file such Forms,  including a "Management's  Discussion and Analysis
of  Financial  Condition  and Results of  Operations"  and,  with respect to the
annual information only, a report thereon by the Company's certified independent
accountants  and (ii) all  financial  information  that would be  required to be
included in a Form 8-K filed with the SEC if the Company  were  required to file
such reports. In addition,  whether or not required by the rules and regulations
of the SEC,  the Company  will file a copy of all such  information  and reports
with the SEC for public  availability  (unless  the SEC will not  accept  such a
filing)  and make such  information  available  to  investors  who request it in
writing.  Notwithstanding anything to the contrary contained herein, the Trustee
shall  have no  duty to  review  such  documents  for  purposes  of  determining
compliance with any provisions of this Indenture.

                 SECTION  1006.  Statement  as to  Compliance.  The Company will
deliver to the  Trustee,  within 120 days after the end of each fiscal  year,  a
brief  certificate from the principal  executive  officer,  principal  financial
officer  or  principal  accounting  officer  as to his or her  knowledge  of the
Company's compliance with all conditions and covenants under this Indenture and,
in the event of any noncompliance,  specifying such noncompliance and the nature

                                      -44-

and status thereof.  For purposes of this Section 1006, such compliance shall be
determined  without regard to any period of grace or requirement of notice under
this Indenture.

                 SECTION 1007. Additional Amounts. If any Securities of a series
provide  for the payment of  Additional  Amounts,  the  Company  will pay to the
Holder  of any  Security  of such  series  or any  coupon  appertaining  thereto
Additional  Amounts as may be specified as contemplated by Section 301. Whenever
in this  Indenture  there is  mentioned,  in any  context  except in the case of
Section  502(1),  the payment of the principal of or any premium or interest on,
or in respect of, any Security of any series or payment of any related coupon or
the net proceeds received on the sale or exchange of any Security of any series,
such  mention  shall be deemed to include  mention of the payment of  Additional
Amounts provided by the terms of such series established pursuant to Section 301
to the extent that,  in such context,  Additional  Amounts are, were or would be
payable in respect  thereof  pursuant to such terms and  express  mention of the
payment of Additional Amounts (if applicable) in any provisions hereof shall not
be construed as excluding  Additional  Amounts in those provisions  hereof where
such express mention is not made.

                 Except as otherwise  specified as  contemplated by Section 301,
if the Securities of a series provide for the payment of Additional  Amounts, at
least 20 days  prior to the first  Interest  Payment  Date with  respect to that
series of Securities (or if the Securities of that series will not bear interest
prior to Maturity, the first day on which a payment of principal and any premium
is made),  and at least 10 days prior to each date of payment of  principal  and
any premium or interest if there has been any change with respect to the matters
set forth in the below-mentioned Officers' Certificate, the Company will furnish
the Trustee and the Company's  principal Paying Agent or Paying Agents, if other
than the Trustee, with an Officers' Certificate instructing the Trustee and such
Paying  Agent or Paying  Agents  whether  such  payment of  principal of and any
premium or interest on the Securities of that series shall be made to Holders of
Securities  of that  series or any  related  coupons  who are not United  States
persons without  withholding  for or on account of any tax,  assessment or other
governmental  charge  described  in the  Securities  of the series.  If any such
withholding shall be required,  then such Officers' Certificate shall specify by
country the  amount,  if any,  required to be withheld on such  payments to such
Holders of Securities of that series or related coupons and the Company will pay
to the Trustee or such Paying Agent the Additional Amounts required by the terms
of such  Securities.  In the event that the Trustee or any Paying Agent,  as the
case may be,  shall not so receive  the  above-mentioned  certificate,  then the
Trustee  or such  Paying  Agent  shall be  entitled  (i) to assume  that no such
withholding or deduction is required with respect to any payment of principal or
interest with respect to any Securities of a series or related  coupons until it
shall  have  received  a  certificate  advising  otherwise  and (ii) to make all
payments of principal and interest with respect to the Securities of a series or
related coupons without  withholding or deductions until otherwise advised.  The
Company covenants to indemnify the Trustee and any Paying Agent for, and to hold
them  harmless  against,  any loss,  liability  or expense  reasonably  incurred
without  negligence  or bad faith on their part arising out of or in  connection
with  actions  taken or omitted by any of them or in reliance  on any  Officers'
Certificate  furnished  pursuant to this Section or in reliance on the Company's
not furnishing such an Officers' Certificate.

                 SECTION 1008. Waiver of Certain Covenants. The Company may omit
in any particular  instance to comply with any term,  provision or condition set
forth in Sections 1004 or 1005, if before or after the time for such  compliance
the  Holders  of at least a  majority  in  principal  amount of all  outstanding
Securities of such series, by Act of such Holders,  either waive such compliance
in such instance or generally waive  compliance with such covenant or condition,
but no such waiver shall extend to or affect such  covenant or condition  except
to the  extent  so  expressly  waived,  and,  until  such  waiver  shall  become
effective,  the  obligations  of the  Company  and the duties of the  Trustee in
respect of any such term,  provision or condition shall remain in full force and
effect.

                                      -45-

                                 ARTICLE ELEVEN

                            REDEMPTION OF SECURITIES

                 SECTION  1101.  Applicability  of  Article.  Securities  of any
series which are redeemable  before their Stated Maturity shall be redeemable in
accordance  with their terms and (except as otherwise  specified as contemplated
by Section 301 for Securities of any series) in accordance with this Article.

                 SECTION  1102.  Election  to  Redeem;  Notice to  Trustee.  The
election  of the  Company  to redeem any  Securities  shall be  evidenced  by or
pursuant to a Board Resolution. In case of any redemption at the election of the
Company of less than all of the Securities of any series,  the Company shall, at
least 45 days prior to the giving of the notice of  redemption  in Section  1104
(unless a shorter  notice  shall be  satisfactory  to the  Trustee),  notify the
Trustee of such  Redemption  Date and of the  principal  amount of Securities of
such series to be redeemed. In the case of any redemption of Securities prior to
the expiration of any  restriction on such  redemption  provided in the terms of
such  Securities or elsewhere in this  Indenture,  the Company shall furnish the
Trustee  with  an  Officers'   Certificate   evidencing   compliance  with  such
restriction.

                 SECTION  1103.   Selection  by  Trustee  of  Securities  to  Be
Redeemed.  If less than all the  Securities of any series issued on the same day
with the same terms are to be redeemed, the particular Securities to be redeemed
shall be  selected  not more than 60 days  prior to the  Redemption  Date by the
Trustee, from the Outstanding Securities of such series issued on such date with
the same terms not  previously  called  for  redemption,  by such  method as the
Trustee shall deem fair and  appropriate and which may provide for the selection
for redemption of portions  (equal to the minimum  authorized  denomination  for
Securities  of that series or any integral  multiple  thereof) of the  principal
amount of  Securities of such series of a  denomination  larger than the minimum
authorized denomination for Securities of that series.

                 The Trustee shall promptly  notify the Company and the Security
Registrar  (if other than  itself) in writing  of the  Securities  selected  for
redemption and, in the case of any Securities  selected for partial  redemption,
the principal amount thereof to be redeemed.

                 For  all  purposes  of  this  Indenture,   unless  the  context
otherwise  requires,  all  provisions  relating to the  redemption of Securities
shall  relate,  in the case of any Security  redeemed or to be redeemed  only in
part, to the portion of the principal  amount of such Security which has been or
is to be redeemed.

                 SECTION 1104. Notice of Redemption.  Notice of redemption shall
be given in the manner  provided in Section 106 and as may be further  specified
in an indenture supplemental hereto, not less than 30 days nor more than 60 days
prior to the Redemption Date,  unless a shorter period is specified by the terms
of such series established pursuant to Section 301, to each Holder of Securities
to be redeemed, but failure to give such notice in the manner herein provided to
the Holder of any Security  designated  for redemption as a whole or in part, or
any defect in the notice to any such  Holder,  shall not affect the  validity of
the  proceedings  for the  redemption  of any other  such  Security  or  portion
thereof.

                 Any  notice  that  is  mailed  to  the  Holders  of  Registered
Securities in the manner herein provided shall be conclusively  presumed to have
been duly given, whether or not such Holders receive such notice.

                 All notices of redemption shall state:

                           (1) the Redemption Date,

                           (2) the  Redemption  Price,  accrued  interest to the
         Redemption  Date  payable as  provided  in Section  1106,  if any,  and
         Additional Amounts, if any,

                                      -46-

                           (3) if less than all  Outstanding  Securities  of any
         series are to be  redeemed,  the  identification  (and,  in the case of
         partial redemption, the principal amount) of the particular Security or
         Securities to be redeemed,

                           (4) in case any  Security  is to be  redeemed in part
         only, the notice which relates to such Security shall state that on and
         after the Redemption Date, upon surrender of such Security,  the holder
         will  receive,   without  charge,  a  new  Security  or  Securities  of
         authorized  denominations  for the principal  amount thereof  remaining
         unredeemed,

                           (5) that on the Redemption Date the Redemption  Price
         and accrued  interest  to the  Redemption  Date  payable as provided in
         Section  1106,  if any,  will  become  due and  payable  upon each such
         Security,  or the portion  thereof,  to be redeemed and, if applicable,
         that interest thereon shall cease to accrue on and after said date,

                           (6)  the  Place  or  Places  of  Payment  where  such
         Securities,  together in the case of Bearer Securities with all coupons
         appertaining  thereto,  if any, maturing after the Redemption Date, are
         to be  surrendered  for  payment of the  Redemption  Price and  accrued
         interest, if any, or for conversion,

                           (7) that the  redemption  is for a sinking  fund,  if
         such is the case,

                           (8) that unless  otherwise  specified in such notice,
         Bearer  Securities of any series,  if any,  surrendered  for redemption
         must  be  accompanied  by  all  coupons  maturing   subsequent  to  the
         Redemption  Date or the  amount of any such  missing  coupon or coupons
         will  be  deducted  from  the  Redemption  Price,  unless  security  or
         indemnity  satisfactory to the Company, the Trustee for such series and
         any Paying Agent is furnished,

                           (9) if  Bearer  Securities  of any  series  are to be
         redeemed  and any  Registered  Securities  of such series are not to be
         redeemed, and if such Bearer Securities may be exchanged for Registered
         Securities not subject to redemption on this  Redemption  Date pursuant
         to Section  305 or  otherwise,  the last  date,  as  determined  by the
         Company, on which such exchanges may be made,

                           (10) the CUSIP number of such Security, if any, and

                           (11) if  applicable,  that a Holder of Securities who
         desires  to  convert   Securities  for  redemption   must  satisfy  the
         requirements  for  conversion  contained in such  Securities,  the then
         existing  conversion  price  or rate,  and the  date and time  when the
         option to convert shall expire.

                 Notice of  redemption  of  Securities  to be redeemed  shall be
given by the Company or, at the  Company's  request,  by the Trustee in the name
and at the expense of the Company.

                 SECTION 1105. Deposit of Redemption Price. On or prior to 11:00
am (Boston  time) on any  Redemption  Date,  the Company  shall deposit with the
Trustee or with a Paying  Agent (or,  if the Company is acting as its own Paying
Agent,  which it may not do in the case of a sinking fund payment  under Article
Twelve,  segregate  and hold in trust as provided in Section  1003) an amount of
money in the  currency  or  currencies,  currency  unit or  units  or  composite
currency  or  currencies  in which the  Securities  of such  series are  payable
(except as otherwise  specified  pursuant to Section 301 for the  Securities  of
such series)  sufficient to pay on the Redemption Date the Redemption  Price of,
and (except if the  Redemption  Date shall be an Interest  Payment Date) accrued
interest on, all the Securities or portions  thereof which are to be redeemed on
that date.

                 SECTION 1106.  Securities Payable on Redemption Date. Notice of
redemption  having been given as  aforesaid,  the  Securities  so to be redeemed
shall, on the Redemption  Date,  become due and payable at the Redemption  Price
therein  specified  in the  currency or  currencies,  currency  unit or units or
composite  currency or  currencies  in which 

                                      -47-

the  Securities  of such  series  are  payable  (except as  otherwise  specified
pursuant  to Section  301 for the  Securities  of such  series)  (together  with
accrued interest,  if any, to the Redemption Date), and from and after such date
(unless the Company  shall  default in the payment of the  Redemption  Price and
accrued  interest) such  Securities  shall,  if the same were  interest-bearing,
cease to bear  interest and the coupons for such  interest  appertaining  to any
Bearer Securities so to be redeemed,  except to the extent provided below, shall
be void.  Upon surrender of any such Security for redemption in accordance  with
said notice,  together with all coupons, if any,  appertaining  thereto maturing
after the  Redemption  Date,  such Security  shall be paid by the Company at the
Redemption  Price,  together with accrued  interest,  if any, to the  Redemption
Date;  provided,  however,  that  installments of interest on Bearer  Securities
whose  Stated  Maturity is on or prior to the  Redemption  Date shall be payable
only at an office  or agency  located  outside  the  United  States  (except  as
otherwise  provided  in  Section  1002)  and,  unless  otherwise   specified  as
contemplated by Section 301, only upon presentation and surrender of coupons for
such  interest;  and provided  further that,  except as otherwise  provided with
respect to Securities  convertible into Common Shares or Preferred Shares of the
Company, installments of interest on Registered Securities whose Stated Maturity
is on or prior to the  Redemption  Date shall be payable to the  Holders of such
Securities,  or one or more  Predecessor  Securities,  registered as such at the
close of business on the relevant  Record Dates according to their terms and the
provisions of Section 307.

                 If any Bearer Security  surrendered for redemption shall not be
accompanied by all appurtenant  coupons maturing after the Redemption Date, such
Security may be paid after  deducting from the Redemption  Price an amount equal
to the face amount of all such missing coupons, or the surrender of such missing
coupon or  coupons  may be waived by the  Company  and the  Trustee  if there be
furnished to them such security or indemnity as they may require to save each of
them and any Paying Agent  harmless.  If thereafter  the Holder of such Security
shall  surrender to the Trustee or any Paying  Agent any such missing  coupon in
respect of which a  deduction  shall have been made from the  Redemption  Price,
such  Holder  shall be entitled  to receive  the amount so  deducted;  provided,
however, that interest represented by coupons shall be payable only at an office
or agency  located  outside the United States  (except as otherwise  provided in
Section 1002) and,  unless  otherwise  specified as contemplated by Section 301,
only upon presentation and surrender of those coupons.

                  If any  Security  called for  redemption  shall not be so paid
upon  surrender  thereof for  redemption,  the principal  (and premium,  if any)
shall,  until paid,  bear interest from the Redemption Date at the rate borne by
the Security.

                 SECTION  1107.  Securities  Redeemed  in Part.  Any  Registered
Security  which is to be redeemed  only in part  (pursuant to the  provisions of
this Article or of Article  Twelve) shall be  surrendered  at a Place of Payment
therefor (with,  if the Company or the Trustee so requires,  due endorsement by,
or a written  instrument of transfer in form satisfactory to the Company and the
Trustee duly executed by, the Holder thereof or his attorney duly  authorized in
writing) and the Company shall execute and the Trustee  shall  authenticate  and
deliver to the Holder of such Security  without service charge a new Security or
Securities of the same series,  of any authorized  denomination  as requested by
such Holder in  aggregate  principal  amount  equal to and in  exchange  for the
unredeemed portion of the principal of the Security so surrendered.

                                 ARTICLE TWELVE

                                  SINKING FUNDS

                 SECTION 1201.  Applicability of Article. The provisions of this
Article shall be applicable to any sinking fund for the retirement of Securities
of a series  except as otherwise  specified as  contemplated  by Section 301 for
Securities of such series.

                 The minimum amount of any sinking fund payment  provided for by
the terms of  Securities  of any series is herein  referred  to as a  "mandatory
sinking fund payment", and any payment in excess of such minimum amount provided
for by the terms of such  Securities  of any series is herein  referred to as an
"optional sinking fund payment".  If provided for by the terms of any Securities
of any series,  the cash amount of any  mandatory  sinking  fund  payment 

                                      -48-

may be subject to  reduction  as provided in Section  1202.  Each  sinking  fund
payment  shall be  applied  to the  redemption  of  Securities  of any series as
provided for by the terms of Securities of such series.

                 SECTION  1202.  Satisfaction  of  Sinking  Fund  Payments  with
Securities. The Company may, in satisfaction of all or any part of any mandatory
sinking fund payment with  respect to the  Securities  of a series,  (1) deliver
Outstanding  Securities  of such series  (other than any  previously  called for
redemption)  together in the case of any Bearer  Securities  of such series with
all unmatured coupons  appertaining thereto and (2) apply as a credit Securities
of such series  which have been  redeemed  either at the election of the Company
pursuant to the terms of such Securities or through the application of permitted
optional  sinking fund  payments  pursuant to the terms of such  Securities,  as
provided  for by the terms of such  Securities,  or which  have  otherwise  been
acquired by the Company;  provided that such  Securities so delivered or applied
as a credit have not been  previously  so  credited.  Such  Securities  shall be
received  and  credited  for  such  purpose  by the  Trustee  at the  applicable
Redemption Price specified in such Securities for redemption  through  operation
of the sinking fund and the amount of such mandatory  sinking fund payment shall
be reduced accordingly.

                 SECTION 1203.  Redemption of Securities  for Sinking Fund.  Not
less than 60 days prior to each sinking fund payment date for  Securities of any
series,  the  Company  will  deliver  to the  Trustee an  Officers'  Certificate
specifying  the amount of the next  ensuing  mandatory  sinking fund payment for
that series pursuant to the terms of that series,  the portion thereof,  if any,
which is to be  satisfied  by payment  of cash in the  currency  or  currencies,
currency  unit or  units or  composite  currency  or  currencies  in  which  the
Securities of such series are payable (except as otherwise specified pursuant to
Section 301 for the Securities of such series) and the portion thereof,  if any,
which is to be satisfied by delivering  and crediting  Securities of that series
pursuant to Section 1202, and the optional  amount,  if any, to be added in cash
to the next ensuing mandatory sinking fund payment, and will also deliver to the
Trustee any  Securities  to be so  delivered  and  credited.  If such  Officers'
Certificate  shall  specify an  optional  amount to be added in cash to the next
ensuing mandatory sinking fund payment, the Company shall thereupon be obligated
to pay the amount  therein  specified.  Not less than 30 days  before  each such
sinking fund payment date the Trustee shall select the Securities to be redeemed
upon such sinking fund payment date in the manner  specified in Section 1103 and
cause  notice of the  redemption  thereof  to be given in the name of and at the
expense of the  Company in the manner  provided  in Section  1104.  Such  notice
having been duly given, the redemption of such Securities shall be made upon the
terms and in the manner stated in Sections 1106 and 1107.

                                ARTICLE THIRTEEN

                       REPAYMENT AT THE OPTION OF HOLDERS

                 SECTION 1301. Applicability of Article. Repayment of Securities
of any series  before  their  Stated  Maturity at the option of Holders  thereof
shall be made in  accordance  with the  terms of such  Securities,  if any,  and
(except as otherwise specified by the terms of such series established  pursuant
to Section 301) in accordance with this Article.

                 SECTION 1302. Repayment of Securities. Securities of any series
subject to  repayment  in whole or in part at the option of the Holders  thereof
will, unless otherwise provided in the terms of such Securities,  be repaid at a
price equal to the principal  amount  thereof,  together with interest,  if any,
thereon  accrued to the Repayment  Date specified in or pursuant to the terms of
such Securities.  The Company  covenants that on or before the Repayment Date it
will  deposit  with the  Trustee or with a Paying  Agent (or,  if the Company is
acting as its own  Paying  Agent,  segregate  and hold in trust as  provided  in
Section 1003) an amount of money in the currency or currencies, currency unit or
units or composite currency or currencies in which the Securities of such series
are  payable  (except as  otherwise  specified  pursuant  to Section 301 for the
Securities of such series)  sufficient to pay the principal  (or, if so provided
by the terms of the Securities of any series, a percentage of the principal) of,
and (except if the  Repayment  Date shall be an Interest  Payment  Date) accrued
interest on, all the Securities or portions  thereof,  as the case may be, to be
repaid on such date.

                                      -49-

                 SECTION  1303.  Exercise  of Option.  Securities  of any series
subject  to  repayment  at the option of the  Holders  thereof  will  contain an
"Option to Elect Repayment" form on the reverse of such Securities. In order for
any Security to be repaid at the option of the Holder,  the Trustee must receive
at the Place of Payment therefor  specified in the terms of such Security (or at
such other place or places of which the  Company  shall from time to time notify
the Holders of such  Securities) not earlier than 60 days nor later than 30 days
prior to the  Repayment  Date (1) the Security so providing  for such  repayment
together with the "Option to Elect  Repayment"  form on the reverse thereof duly
completed by the Holder or by the Holder's  attorney duly  authorized in writing
or (2) a telegram,  telex, facsimile transmission or a letter from a member of a
national securities exchange, or the National Association of Securities Dealers,
Inc.  ("NASD"),  or a  commercial  bank or trust  company in the  United  States
setting  forth the name of the Holder of the Security,  the principal  amount of
the  Security,  the  principal  amount of the  Security to be repaid,  the CUSIP
number,  if any,  or a  description  of the tenor and terms of the  Security,  a
statement that the option to elect  repayment is being  exercised  thereby and a
guarantee that the Security to be repaid,  together with the duly completed form
entitled  "Option to Elect  Repayment" on the reverse of the  Security,  will be
received by the Trustee not later than the fifth  Business Day after the date of
such telegram, telex, facsimile transmission or letter; provided,  however, that
such telegram,  telex,  facsimile transmission or letter shall only be effective
if such  Security  and form duly  completed  are received by the Trustee by such
fifth Business Day. If less than the entire principal amount of such Security is
to be repaid in accordance with the terms of such Security, the principal amount
of such Security to be repaid,  in increments  of the minimum  denomination  for
Securities of such series, and the denomination or denominations of the Security
or Securities to be issued to the Holder for the portion of the principal amount
of such Security  surrendered that is not to be repaid,  must be specified.  The
principal  amount of any security  providing  for repayment at the option of the
Holder  thereof  may not be repaid in part if,  following  such  repayment,  the
unpaid  principal  amount  of such  Security  would  be less  than  the  minimum
authorized denomination of Securities of the series of which such Security to be
repaid  is a part.  Except  as  otherwise  may be  provided  by the terms of any
Security  providing for repayment at the option of the Holder thereof,  exercise
of the repayment option by the Holder shall be irrevocable  unless waived by the
Company.

                 SECTION 1304.  When Securities  Presented for Repayment  Become
Due and Payable.  If  Securities  of any series  providing  for repayment at the
option of the Holders  thereof shall have been  surrendered  as provided in this
Article and as provided  by or  pursuant to the terms of such  Securities,  such
Securities  or the  portions  thereof,  as the case may be, to be  repaid  shall
become due and payable and shall be paid by the  Company on the  Repayment  Date
therein  specified,  and on and after such  Repayment  Date  (unless the Company
shall  default in the payment of such  Securities on such  Repayment  Date) such
Securities shall, if the same were interest-bearing,  cease to bear interest and
the coupons for such  interest  appertaining  to any Bearer  Securities so to be
repaid,  except to the extent provided  below,  shall be void. Upon surrender of
any such  Security for repayment in accordance  with such  provisions,  together
with all coupons,  if any,  appertaining  thereto  maturing  after the Repayment
Date, the principal amount of such Security so to be repaid shall be paid by the
Company,  together  with  accrued  interest,  if  any,  to the  Repayment  Date;
provided,  however,  that coupons  whose  Stated  Maturity is on or prior to the
Repayment Date shall be payable only at an office or agency located  outside the
United  States  (except  as  otherwise  provided  in Section  1002) and,  unless
otherwise  specified  pursuant  to  Section  301,  only  upon  presentation  and
surrender of such coupons;  and provided further that, in the case of Registered
Securities,  installments  of interest,  if any, whose Stated  Maturity is on or
prior to the  Repayment  Date shall be payable  (but without  interest  thereon,
unless the Company shall default in the payment  thereof) to the Holders of such
Securities,  or one or more  Predecessor  Securities,  registered as such at the
close of business on the relevant  Record Dates according to their terms and the
provisions of Section 307.

                 If any Bearer  Security  surrendered for repayment shall not be
accompanied by all appurtenant  coupons  maturing after the Repayment Date, such
Security  may be paid  after  deducting  from the  amount  payable  therefor  as
provided in Section  1302 an amount equal to the face amount of all such missing
coupons, or the surrender of such missing coupon or coupons may be waived by the
Company and the Trustee if there be furnished to them such security or indemnity
as they may  require  to save each of them and any  Paying  Agent  harmless.  If
thereafter  the Holder of such  Security  shall  surrender to the Trustee or any
Paying Agent any such missing coupon in respect of which a deduction  shall have
been made as provided in the preceding  sentence,  such Holder shall be entitled
to receive the amount so deducted;  provided, however, that interest represented
by coupons  shall be payable  only at an office or agency  located  

                                      -50-

outside the United  States  (except as otherwise  provided in Section 1002) and,
unless   otherwise   specified  as   contemplated  by  Section  301,  only  upon
presentation and surrender of those coupons.

                 If  the  principal  amount  of  any  Security  surrendered  for
repayment shall not be so repaid upon surrender  thereof,  such principal amount
(together with interest,  if any, thereon accrued to such Repayment Date) shall,
until paid,  bear interest  from the  Repayment  Date at the rate of interest or
Yield to Maturity (in the case of Original Issue Discount  Securities) set forth
in such Security.

                 SECTION 1305.  Securities Repaid in Part. Upon surrender of any
Registered  Security  which is to be  repaid in part  only,  the  Company  shall
execute and the  Trustee  shall  authenticate  and deliver to the Holder of such
Security,  without  service  charge  and at the  expense of the  Company,  a new
Registered  Security  or  Securities  of the  same  series,  of  any  authorized
denomination  specified by the Holder, in an aggregate principal amount equal to
and in exchange for the portion of the principal of such Security so surrendered
which is not to be repaid.


                                ARTICLE FOURTEEN

                       DEFEASANCE AND COVENANT DEFEASANCE

                 SECTION 1401.  Applicability  of Article;  Company's  Option to
Effect Defeasance or Covenant Defeasance. If, pursuant to Section 301, provision
is made for either or both of (a)  defeasance  of the  Securities of or within a
series under  Section 1402 or (b) covenant  defeasance  of the  Securities of or
within a series  under  Section  1403,  then the  provisions  of such Section or
Sections, as the case may be, together with the other provisions of this Article
(with such  modifications  thereto as may be  specified  pursuant to Section 301
with respect to any Securities),  shall be applicable to such Securities and any
coupons  appertaining  thereto,  and the  Company  may at its  option  by  Board
Resolution,  at any  time,  with  respect  to such  Securities  and any  coupons
appertaining thereto, elect to have Section 1402 (if applicable) or Section 1403
(if  applicable)  be  applied to such  Outstanding  Securities  and any  coupons
appertaining thereto upon compliance with the conditions set forth below in this
Article.

                 SECTION  1402.  Defeasance  and  Discharge.  Upon the Company's
exercise of the above  option  applicable  to this  Section  with respect to any
Securities  of or  within a  series,  the  Company  shall be deemed to have been
discharged from its obligations with respect to such Outstanding  Securities and
any coupons appertaining thereto on the date the conditions set forth in Section
1404  are  satisfied  (hereinafter,   "defeasance").   For  this  purpose,  such
defeasance  means that the Company  shall be deemed to have paid and  discharged
the entire  indebtedness  represented  by such  Outstanding  Securities  and any
coupons   appertaining   thereto,   which  shall  thereafter  be  deemed  to  be
"Outstanding"  only for the purposes of Section  1405 and the other  Sections of
this Indenture  referred to in clauses (A) and (B) below,  and to have satisfied
all of its other obligations under such Securities and any coupons  appertaining
thereto  and  this  Indenture   insofar  as  such  Securities  and  any  coupons
appertaining  thereto  are  concerned  (and the  Trustee,  at the expense of the
Company,  shall execute proper instruments  acknowledging the same),  except for
the  following  which shall  survive  until  otherwise  terminated or discharged
hereunder:  (A) the  rights of Holders of such  Outstanding  Securities  and any
coupons appertaining thereto to receive, solely from the trust fund described in
Section 1404 and as more fully set forth in such Section, payments in respect of
the principal of (and premium, if any) and interest,  if any, on such Securities
and any  coupons  appertaining  thereto  when  such  payments  are due,  (B) the
Company's  obligations  with respect to such Securities under Sections 305, 306,
1002 and 1003 and with respect to the payment of Additional  Amounts, if any, on
such Securities as contemplated by Section 1007, (C) the rights, powers, trusts,
duties and  immunities of the Trustee  hereunder and (D) this Article  Fourteen.
Subject to compliance with this Article  Fourteen,  the Company may exercise its
option under this Section notwithstanding the prior exercise of its option under
Section  1403 with  respect  to such  Securities  and any  coupons  appertaining
thereto.

                 SECTION 1403. Covenant Defeasance.  Upon the Company's exercise
of the above option applicable to this Section with respect to any Securities of
or within a series,  the Company  shall be released from its  obligations  under
Sections  1004  and  1005  and,  if  specified  pursuant  to  Section  301,  its
obligations  under  any  other  covenant,   with  

                                      -51-

respect to such Outstanding  Securities and any coupons  appertaining thereto on
and  after  the date the  conditions  set forth in  Section  1404 are  satisfied
(hereinafter,  "covenant  defeasance"),  and  such  Securities  and any  coupons
appertaining  thereto shall thereafter be deemed to be not "Outstanding" for the
purposes of any direction, waiver, consent or declaration or Act of Holders (and
the  consequences  of any thereof) in connection  with Sections 1004 and 1005 or
such other covenant, but shall continue to be deemed "Outstanding" for all other
purposes hereunder.  For this purpose, such covenant defeasance means that, with
respect to such Outstanding Securities and any coupons appertaining thereto, the
Company  may omit to comply with and shall have no  liability  in respect of any
term,  condition  or  limitation  set forth in any such  Section  or such  other
covenant,  whether directly or indirectly,  by reason of any reference elsewhere
herein to any such  Section or such other  covenant or by reason of reference in
any such Section or such other covenant to any other provision  herein or in any
other  document and such omission to comply shall not constitute a default or an
Event of Default  under Section  501(4) or 501(9) or otherwise,  as the case may
be, but except as specified  above,  the  remainder of this  Indenture  and such
Securities and any coupons appertaining thereto shall be unaffected thereby.

                  SECTION 1404. Conditions to Defeasance or Covenant Defeasance.
The following  shall be the conditions to application of Section 1402 or Section
1403 to any  Outstanding  Securities  of or  within  a  series  and any  coupons
appertaining thereto:

                           (a) The Company shall  irrevocably  have deposited or
         caused to be deposited with the Trustee (or another trustee  satisfying
         the  requirements  of Section  607 who shall  agree to comply  with the
         provisions of this Article Fourteen applicable to it) as trust funds in
         trust for the purpose of making the  following  payments,  specifically
         pledged as security  for, and  dedicated  solely to, the benefit of the
         Holders of such Securities and any coupons appertaining thereto, (1) an
         amount in such  currency,  currencies  or  currency  unit in which such
         Securities and any coupons  appertaining  thereto are then specified as
         payable at Stated  Maturity)  which  through the  scheduled  payment of
         principal  and  interest in respect  thereof in  accordance  with their
         terms will  provide,  not later than one day before the due date of any
         payment of principal of (and premium, if any) and interest,  if any, on
         such Securities and any coupons appertaining thereto, or (2) Government
         Obligations  applicable  to such  Securities  and coupons  appertaining
         thereto  (determined  on the  basis  of  the  currency,  currencies  or
         currency unit in which such Securities and coupons appertaining thereto
         are then  specified as payable at Stated  Maturity)  which  through the
         scheduled  payment of  principal  and  interest  in respect  thereof in
         accordance with their terms will provide, not later than one day before
         the due date of any payment of principal of (and  premium,  if any) and
         interest,  if any,  on such  Securities  and any  coupons  appertaining
         thereto, money in an amount, or (3) a combination thereof in an amount,
         sufficient,   in  the  opinion  of  a  nationally  recognized  firm  of
         independent  public  accountants  expressed in a written  certification
         thereof delivered to the Trustee, to pay and discharge, and which shall
         be applied by the  Trustee  (or other  qualifying  trustee)  to pay and
         discharge,  (i) the principal of (and premium, if any) and interest, if
         any,  on  such  Outstanding  Securities  and any  coupons  appertaining
         thereto on the Stated  Maturity of such  principal  or  installment  of
         principal or interest and (ii) any  mandatory  sinking fund payments or
         analogous  payments  applicable to such Outstanding  Securities and any
         coupons  appertaining thereto on the day on which such payments are due
         and payable in accordance  with the terms of this Indenture and of such
         Securities and any coupons appertaining thereto.

                           (b) Such defeasance or covenant  defeasance shall not
         result in a breach or violation of, or constitute a default under, this
         Indenture or any other  material  agreement or  instrument to which the
         Company is a party or by which it is bound.

                           (c) No Event of Default or event which with notice or
         lapse of time or both would  become an Event of Default with respect to
         such  Securities  and  any  coupons  appertaining  thereto  shall  have
         occurred and be continuing  on the date of such deposit or,  insofar as
         Sections 501(6) and 501(7) are concerned, at any time during the period
         ending  on the  91st  day  after  the date of such  deposit  (it  being
         understood that this condition shall not be deemed  satisfied until the
         expiration of such period).

                                      -52-

                           (d) In the case of an election  under  Section  1402,
         the Company  shall have  delivered to the Trustee an Opinion of Counsel
         stating  that (i) the  Company  has  received  from,  or there has been
         published by, the Internal Revenue Service a ruling,  or (ii) since the
         date of  execution  of this  Indenture,  there has been a change in the
         applicable  Federal  income tax law, in either case to the effect that,
         and based thereon such opinion shall confirm that,  the Holders of such
         Outstanding  Securities and any coupons  appertaining  thereto will not
         recognize  income,  gain or loss for Federal  income tax  purposes as a
         result of such  defeasance and will be subject to Federal income tax on
         the same  amounts,  in the same  manner  and at the same times as would
         have been the case if such defeasance had not occurred.

                           (e) In the case of an election  under  Section  1403,
         the Company  shall have  delivered to the Trustee an Opinion of Counsel
         to the effect that the Holders of such  Outstanding  Securities and any
         coupons  appertaining  thereto will not recognize income,  gain or loss
         for Federal income tax purposes as a result of such covenant defeasance
         and will be subject to Federal  income tax on the same amounts,  in the
         same  manner  and at the same times as would have been the case if such
         covenant defeasance had not occurred.

                           (f) The Company  shall have  delivered to the Trustee
         an Officers'  Certificate and an Opinion of Counsel,  each stating that
         all conditions  precedent to the  defeasance  under Section 1402 or the
         covenant  defeasance  under Section 1403 (as the case may be) have been
         complied  with and an Opinion of Counsel to the effect  that either (i)
         as a result  of a  deposit  pursuant  to  subsection  (a) above and the
         related  exercise of the Company's option under Section 1402 or Section
         1403 (as the  case may be),  registration  is not  required  under  the
         Investment  Company  Act of 1940,  as  amended,  by the  Company,  with
         respect to the trust funds  representing such deposit or by the Trustee
         for such trust funds or (ii) all necessary registrations under said Act
         have been effected.

                           (g)  Notwithstanding  any  other  provisions  of this
         Section,  such defeasance or covenant  defeasance  shall be effected in
         compliance  with any  additional  or  substitute  terms,  conditions or
         limitations which may be imposed on the Company in connection therewith
         pursuant to Section 301.

                  SECTION 1405. Deposited Money and Government Obligations to Be
Held in Trust; Other Miscellaneous Provisions.  Subject to the provisions of the
last paragraph of Section 1003, all money and Government  Obligations  (or other
property as may be provided  pursuant to Section  301)  (including  the proceeds
thereof) deposited with the Trustee (or other qualifying  trustee,  collectively
for purposes of this Section 1405,  the  "Trustee")  pursuant to Section 1404 in
respect of any Outstanding Securities of any series and any coupons appertaining
thereto shall be held in trust and applied by the Trustee,  in  accordance  with
the provisions of such Securities and any coupons  appertaining thereto and this
Indenture,  to  the  payment,  either  directly  or  through  any  Paying  Agent
(including  the  Company  acting as its own  Paying  Agent) as the  Trustee  may
determine,  to the  Holders  of such  Securities  and any  coupons  appertaining
thereto of all sums due and to become due thereon in respect of  principal  (and
premium,  if any) and interest and  Additional  Amounts,  if any, but such money
need not be segregated from other funds except to the extent required by law.

                  Unless  otherwise  specified  with  respect  to  any  Security
pursuant to Section 301, if, after a deposit  referred to in Section 1404(a) has
been made,  (a) the Holder of a Security  in respect of which such  deposit  was
made is  entitled  to, and does,  elect  pursuant to Section 301 or the terms of
such Security to receive  payment in a currency or currency unit other than that
in which the  deposit  pursuant  to Section  1404(a) has been made in respect of
such  Security,  or (b) a Conversion  Event occurs in respect of the currency or
currency  unit in which the deposit  pursuant to Section  1404(a) has been made,
the  indebtedness  represented  by such  Security  and any coupons  appertaining
thereto  shall  be  deemed  to have  been,  and will be,  fully  discharged  and
satisfied  through the payment of the  principal of (and premium,  if any),  and
interest,  if any, on such  Security as the same becomes due out of the proceeds
yielded by converting  (from time to time as specified  below in the case of any
such  election)  the  amount or other  property  deposited  in  respect  of such
Security  into the  currency or  currency  unit in which such  Security  becomes
payable as a result of such election or Conversion Event based on the applicable
market  exchange rate for such currency or currency unit in effect on the 

                                      -53-

second Business Day prior to each payment date, in the case of such an election,
or, the applicable  market exchange rate in effect for such currency or currency
unit (as nearly as feasible), in the case of such Conversion Event.

                  The Company shall pay and  indemnify  the Trustee  against any
tax,  fee  or  other  charge  imposed  on or  assessed  against  the  Government
Obligations  deposited  pursuant to Section 1404 or the  principal  and interest
received in respect  thereof  other than any such tax, fee or other charge which
by law is for the account of the Holders of such Outstanding  Securities and any
coupons appertaining thereto.

                  Anything in this Article to the contrary notwithstanding,  the
Trustee  shall  deliver  or pay to the  Company  from time to time upon  Company
Request any money or Government  Obligations (or other property and any proceeds
therefrom)  held by it as  provided in Section  1404 which,  in the opinion of a
nationally  recognized  firm of independent  public  accountants  expressed in a
written  certification  thereof  delivered to the Trustee,  are in excess of the
amount  thereof  which  would  then be  required  to be  deposited  to  effect a
defeasance  or covenant  defeasance,  as  applicable,  in  accordance  with this
Article.


                                 ARTICLE FIFTEEN

                        MEETINGS OF HOLDERS OF SECURITIES

                  SECTION  1501.  Purposes for Which  Meetings May Be Called.  A
meeting  of Holders  of  Securities  of any series may be called at any time and
from time to time  pursuant to this  Article to make,  give or take any request,
demand,  authorization,  direction,  notice,  consent,  waiver  or other  action
provided by this  Indenture to be made,  given or taken by Holders of Securities
of such series.

                  SECTION  1502.  Call,  Notice and Place of  Meetings.  (a) The
Trustee  may at any time call a meeting of Holders of  Securities  of any series
for any purpose  specified in Section  1501, to be held at such time and at such
place in the City of Boston, or in London as the Trustee shall determine. Notice
of every meeting of Holders of Securities of any series,  setting forth the time
and the place of such  meeting  and in general  terms the action  proposed to be
taken at

                                      -54-

such meeting,  shall be given,  in the manner  provided in Section 106, not less
than 21 nor more than 180 days prior to the date fixed for the meeting.

                  (b) In case  at any  time  the  Company,  pursuant  to a Board
Resolution,  or  the  Holders  of at  least  25%  in  principal  amount  of  the
Outstanding  Securities of any series shall have requested the Trustee to call a
meeting of the Holders of Securities of such series for any purpose specified in
Section 1501, by written request  setting forth in reasonable  detail the action
proposed to be taken at the  meeting,  and the  Trustee  shall not have made the
first  publication of the notice of such meeting within 21 days after receipt of
such request or shall not thereafter  proceed to cause the meeting to be held as
provided herein, then the Company or the Holders of Securities of such series in
the amount above  specified,  as the case may be, may determine the time and the
place in the City of  Boston,  or in London for such  meeting  and may call such
meeting for such purposes by giving notice thereof as provided in subsection (a)
of this Section.

                  SECTION  1503.  Persons  Entitled to Vote at  Meetings.  To be
entitled to vote at any meeting of Holders of Securities of any series, a Person
shall be (1) a Holder of one or more Outstanding  Securities of such series,  or
(2) a Person  appointed  by an  instrument  in  writing as proxy for a Holder or
Holders of one or more  Outstanding  Securities of such series by such Holder or
Holders. The only Persons who shall be entitled to be present or to speak at any
meeting of Holders of Securities of any series shall be the Persons  entitled to
vote at such meeting and their counsel,  any  representatives of the Trustee and
its counsel and any representatives of the Company and its counsel.

                  SECTION 1504.  Quorum;  Action. The Persons entitled to vote a
majority in principal  amount of the  Outstanding  Securities  of a series shall
constitute  a quorum  for a meeting of Holders  of  Securities  of such  series;
provided,  however,  that if any  action  is to be  taken at such  meeting  with
respect to a consent or waiver which this

                                      -55-

Indenture  expressly  provides  may be given by the  Holders  of not less than a
specified  percentage  in principal  amount of the  Outstanding  Securities of a
series,  the Persons  entitled to vote such  specified  percentage  in principal
amount of the Outstanding  Securities of such series shall  constitute a quorum.
In the absence of a quorum  within 30 minutes  after the time  appointed for any
such  meeting,  the  meeting  shall,  if  convened  at the request of Holders of
Securities of such series,  be  dissolved.  In any other case the meeting may be
adjourned  for a period of not less than 10 days  determined  by the chairman of
the meeting prior to the adjournment of such meeting. In the absence of a quorum
at any such adjourned  meeting,  such adjourned meeting may be further adjourned
for a period  of not less  than 10 days as  determined  by the  chairman  of the
meeting  prior to the  adjournment  of such  adjourned  meeting.  Notice  of the
reconvening  of any  adjourned  meeting  shall be given as  provided  in Section
1502(a), except that such notice need be given only once not less than five days
prior to the date on which the meeting is scheduled to be reconvened.  Notice of
the  reconvening of any adjourned  meeting shall state expressly the percentage,
as provided above, of the principal amount of the Outstanding Securities of such
series which shall constitute a quorum.

                  Except  as  limited  by  the  proviso  to  Section   902,  any
resolution  presented to a meeting or adjourned meeting duly reconvened at which
a quorum is present as aforesaid may be adopted by the  affirmative  vote of the
Holders of a majority in principal amount of the Outstanding  Securities of that
series;  provided,  however,  that,  except as limited by the proviso to Section
902,  any  resolution  with  respect  to  any  request,  demand,  authorization,
direction,  notice,  consent,  waiver  or  other  action  which  this  Indenture
expressly  provides  may be made,  given or taken by the  Holders of a specified
percentage,  which  is  less  than  a  majority,  in  principal  amount  of  the
Outstanding  Securities  of a series may be adopted at a meeting or an adjourned
meeting  duly  reconvened  and at which a quorum is present as  aforesaid by the
affirmative vote of the Holders of such specified percentage in principal amount
of the Outstanding Securities of that series.

                  Any  resolution  passed or  decision  taken at any  meeting of
Holders of Securities  of any series duly held in  accordance  with this Section
shall be binding on all the Holders of Securities of such series and the related
coupons, whether or not present or represented at the meeting.

                 Notwithstanding the foregoing  provisions of this Section 1504,
if any action is to be taken at a meeting of Holders of Securities of any series
with respect to any request, demand, authorization,  direction, notice, consent,
waiver or other action that this Indenture expressly provides may be made, given
or taken by the Holders of a specified  percentage  in  principal  amount of all
Outstanding  Securities  affected thereby,  or of the Holders of such series and
one or more additional series:

                           (i) there shall be no minimum quorum  requirement for
         such meeting; and

                           (ii)  the   principal   amount  of  the   Outstanding
         Securities of such series that vote in favor of such  request,  demand,
         authorization, direction, notice, consent, waiver or other action shall
         be taken into  account in  determining  whether such  request,  demand,
         authorization,  direction,  notice, consent, waiver or other action has
         been made, given or taken under this Indenture.

                 SECTION  1505.  Determination  of Voting  Rights;  Conduct  and
Adjournment of Meetings.

                 (a)  Notwithstanding  any  provisions  of this  Indenture,  the
Trustee may make such  reasonable  regulations  as it may deem advisable for any
meeting of Holders of  Securities  of a series in regard to proof of the holding
of Securities of such series and of the  appointment of proxies and in regard to
the  appointment  and  duties  of  inspectors  of  votes,   the  submission  and
examination  of proxies,  certificates  and other evidence of the right to vote,
and such other  matters  concerning  the conduct of the meeting as it shall deem
appropriate.  Except as otherwise permitted or required by any such regulations,
the holding of Securities shall be proved in the manner specified in Section 104
and the  appointment  of any proxy  shall be proved in the manner  specified  in
Section  104 or by  having  the  signature  of the  Person  executing  the proxy
witnessed or  guaranteed  by any trust  company,  bank or banker  authorized  by
Section 104 to certify to the holding of Bearer Securities. Such regulations may
provide that written instruments appointing 

                                      -56-

proxies,  regular on their face, may be presumed  valid and genuine  without the
proof specified in Section 104 or other proof.

                 (b) The Trustee  shall,  by an instrument in writing  appoint a
temporary chairman of the meeting,  unless the meeting shall have been called by
the Company or by Holders of Securities as provided in Section 1502(b), in which
case the Company or the Holders of Securities of the series calling the meeting,
as the case  may be,  shall in like  manner  appoint  a  temporary  chairman.  A
permanent chairman and a permanent  secretary of the meeting shall be elected by
vote of the  Persons  entitled  to vote a majority  in  principal  amount of the
Outstanding Securities of such series represented at the meeting.

                 (c) At any meeting  each Holder of a Security of such series or
proxy  shall be entitled  to one vote for each  $1,000  principal  amount of the
Outstanding  Securities  of such series held or  represented  by him;  provided,
however,  that no vote shall be cast or counted at any meeting in respect of any
Security  challenged as not Outstanding and ruled by the chairman of the meeting
to be not Outstanding.  The chairman of the meeting shall have no right to vote,
except as a Holder of a Security of such series or proxy.

                  (d) Any  meeting of Holders of  Securities  of any series duly
called  pursuant to Section  1502 at which a quorum is present may be  adjourned
from time to time by Persons  entitled to vote a majority in principal amount of
the Outstanding  Securities of such series  represented at the meeting,  and the
meeting may be held as so adjourned without further notice.

                 SECTION 1506.  Counting Votes and Recording Action of Meetings.
The vote upon any  resolution  submitted to any meeting of Holders of Securities
of any series  shall be by  written  ballots on which  shall be  subscribed  the
signatures   of  the  Holders  of   Securities   of  such  series  or  of  their
representatives  by proxy and the  principal  amounts and serial  numbers of the
Outstanding Securities of such series held or represented by them. The permanent
chairman of the meeting  shall  appoint two  inspectors of votes who shall count
all votes cast at the meeting for or against any  resolution  and who shall make
and file with the secretary of the meeting  their  verified  written  reports in
duplicate of all votes cast at the meeting. A record, at least in duplicate,  of
the  proceedings of each meeting of Holders of Securities of any Series shall be
prepared  by the  secretary  of the  meeting and there shall be attached to said
record the  original  reports of the  inspectors  of votes on any vote by ballot
taken  thereat and  affidavits  by one or more persons  having  knowledge of the
fact,  setting  forth a copy of the notice of the meeting and showing  that said
notice was given as provided in Section 1502 and, if  applicable,  Section 1504.
Each copy  shall be signed  and  verified  by the  affidavits  of the  permanent
chairman  and  secretary  of the meeting and one such copy shall be delivered to
the  Company  and another to the Trustee to be  preserved  by the  Trustee,  the
latter to have attached thereto the ballots voted at the meeting.  Any record so
signed and verified shall be conclusive evidence of the matters therein stated.

                                      -57-

                  This Indenture may be executed in any number of  counterparts,
each of which when so executed  shall be deemed to be an original,  but all such
counterparts shall together constitute but one and the same Indenture.

                  IN WITNESS  WHEREOF,  the  parties  hereto  have  caused  this
Indenture to be duly  executed,  as an instrument  under seal, as of the day and
year first above written.

                                         IRON MOUNTAIN INCORPORATED
                                   
                                   
                                       By:___________________________
                                          Title:
                                   
                                   
                                       ______________________________
                                   
                                   
                                       By:___________________________
                                          Title:
                     


                                      -58-

                                    EXHIBIT A

                             FORMS OF CERTIFICATION


                                   EXHIBIT A-1

               FORM OF CERTIFICATE TO BE GIVEN BY PERSON ENTITLED
                TO RECEIVE BEARER SECURITY OR TO OBTAIN INTEREST
                       PAYABLE PRIOR TO THE EXCHANGE DATE


[Insert title or sufficient description of Securities to be delivered]

                  This is to certify that, as of the date hereof,  and except as
set forth below, the above-captioned  Securities held by you for our account (i)
are owned by person(s)  that are not citizens or residents of the United States,
domestic  partnerships,  domestic corporations or any estate or trust the income
of which is subject to United States federal income  taxation  regardless of its
source ("United States  person(s)"),  (ii) are owned by United States  person(s)
that are (a) foreign branches of United States financial institutions (financial
institutions,   as  defined  in  United  States  Treasury   Regulations  Section
2.165-12(c)(1)(v) are herein referred to as "financial institutions") purchasing
for their own account or for resale, or (b) United States person(s) who acquired
the Securities through foreign branches of United States financial  institutions
and who hold the Securities through such United States financial institutions on
the  date  hereof  (and in  either  case (a) or (b),  each  such  United  States
financial  institutions  hereby agrees,  on its own behalf or through its agent,
that you may advise Health and Rehabilitation Properties Trust or its agent that
such  financial  institutions  will  comply  with the  requirements  of  Section
165(j)(3)(A),  (B) or (C) of the United States Internal Revenue Code of 1986, as
amended, and the regulations thereunder), or (iii) are owned by United States or
foreign  financial  institution(s)  for purposes of resale during the restricted
period  (as  defined  in  United  States  Treasury  Regulations  Section  1.163-
5(c)(1)(i)(D)(7),  and, in addition,  if the owner is a United States or foreign
financial  institutions  described  in clause  (iii) above  (whether or not also
described in clause (i) or (ii)), this is to further certify that such financial
institutions  has not acquired the Securities for purposes of resale directly or
indirectly  to a United States person or to a person within the United States or
its possessions.

                  As used herein,  "United  States"  means the United  States of
America   (including  the  States  and  the  District  of  Columbia);   and  its
"possessions"  include  Puerto Rico, the U.S.  Virgin  Islands,  Guam,  American
Samoa, Wake Island and the Northern Mariana Islands.

                  We  undertake  to advise you  promptly  by tested  telex on or
prior to the date on which you intend to submit your  certification  relating to
the  above-captioned  Securities  held by you for our account in accordance with
your Operating  Procedures if any applicable  statement herein is not correct on
such date,  and in the absence of any such  notification  it may be assumed that
this certification applies as of such date.

                  This  certificate  excepts  and does  not  relate  to  (U.S.$)
_______________ of such interest in the above-captioned Securities in respect of
which we are not able to certify and as to which we  understand  an exchange for
an interest in a Permanent  Global  Security or an exchange  for and delivery of
definitive  Securities (or, if relevant,  collection of any interest)  cannot be
made until we do so certify.

                  We  understand  that  this  certificate  may  be  required  in
connection with certain tax legislation in the United States.  If administrative
or legal  proceedings  are commenced or threatened in connection with which this
certificate  is or would be relevant,  we  irrevocably  authorize you to produce
this certificate or a copy thereof to any interested party in such proceedings.

                                       A-1

Dated:___________________, 19__
[To be dated no earlier than the
15th   day   prior  to  (i)  the
Exchange   Date  or   (ii)   the
relevant  Interest  Payment Date
occurring  prior to the Exchange
Date, as applicable]

                                           [Name of Person Making Certification]

                                           ____________________________________
                                           (Authorized Signatory)
                                           Name:
                                           Title:



                                       A-2

                                   EXHIBIT A-2

                  FORM OF CERTIFICATE TO BE GIVEN BY EUROCLEAR
                AND CEDEL S.A. IN CONNECTION WITH THE EXCHANGE OF
                 A PORTION OF A TEMPORARY GLOBAL SECURITY OR TO
               OBTAIN INTEREST PAYABLE PRIOR TO THE EXCHANGE DATE

                                   CERTIFICATE

[Insert title or sufficient description of Securities to be delivered]

                  This  is  to   certify   that,   based   solely   on   written
certifications  that  we  have  received  in  writing,  by  tested  telex  or by
electronic  transmission  from each of the persons  appearing  in our records as
persons  entitled  to a portion of the  principal  amount  set forth  below (our
"Member  Organizations")  substantially in the form attached  hereto,  as of the
date hereof,  [U.S.$) principal amount of the above-captioned  Securities (i) is
owned by person(s)  that are not  citizens or  residents  of the United  States,
domestic  partnerships,  domestic corporations or any estate or trust the income
of which is subject to United States Federal income  taxation  regardless of its
source ("United  States  person(s)"),  (ii) is owned by United States  person(s)
that are (a) foreign branches of United States financial institutions (financial
institutions,  as defined in U.S. Treasury Regulations Section 1.165-12(c)(1)(v)
are herein  referred to as "financial  institutions")  purchasing  for their own
account  or  for  resale,  or (b)  United  States  person(s)  who  acquired  the
Securities through foreign branches of United States financial  institutions and
who hold the Securities through such United States financial institutions on the
date  hereof (and in either case (a) or (b),  each such  financial  institutions
will comply with the  requirements  of Section  165(j)(3)(A),  (B) or (C) of the
Internal Revenue Code of 1986, as amended, and the regulations  thereunder),  or
(iii) is owned by United States or foreign financial institution(s) for purposes
of resale during the  restricted  period (as defined in United  States  Treasury
Regulations  Section  1.163-5(c)(2)(i)(D)(7)),  and, to the further effect, that
financial  institutions  described  in clause  (iii) above  (whether or not also
described in clause (i) or (ii)) have  certified that they have not acquired the
Securities  for purposes of resale  directly or  indirectly  to a United  States
person or to a person within the United States or its possessions.

                  As used herein,  "United  States"  means the United  States of
America   (including  the  States  and  the  District  of  Columbia);   and  its
"possessions"  include  Puerto Rico, the U.S.  Virgin  Islands,  Guam,  American
Samoa, Wake Island and the Northern Mariana Islands.

                  We  further  certify  that  (i) we are  not  making  available
herewith for exchange (or, if relevant,  collection of any interest) any portion
of the temporary  global Security  representing the  above-captioned  Securities
excepted in the  above-referenced  certificates of Member Organizations and (ii)
as of the date  hereof we have not  received  any  notification  from any of our
Member  Organizations  to the effect  that the  statements  made by such  Member
Organizations  with  respect to any portion of the part  submitted  herewith for
exchange  (or, if relevant,  collection  of any interest) are no longer true and
cannot be relied upon as of the date hereof.

                  We  understand   that  this   certification   is  required  in
connection with certain tax legislation in the United States.  If administrative
or legal  proceedings  are commenced or threatened in connection with which this
certificate  is or would be relevant,  we  irrevocably  authorize you to produce
this certificate or a copy thereof to any interested party in such proceedings.


Dated:___________________, 19__
[To be dated no earlier than the
Exchange Date  or  the  relevant
Interest Payment Date  occurring
prior  to  the Exchange Date, as 
applicable]


                                       A-3

                                           [Morgan Guaranty Trust Company
                                              New York, Brussels Office,]
                                             as Operator of the Euroclear System
                                           [Cedel S.A.]


                                       A-4