EXHIBIT 4.4

                       Armstrong World Industries, Inc.

                                      TO

                      The First National Bank of Chicago
                                    Trustee



                                   INDENTURE
                                        

                         Dated as of December 23, 1998



                         Subordinated Debt Securities

 
                               TABLE OF CONTENTS
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                                                                                                              PAGE
                                                                                                              ----
                                                                                                            
Recitals of the Company...................................................................................     1

                                                            ARTICLE ONE

                                      Definitions and Other Provisions of General Application

Section 101.      Definitions:
                  Act.....................................................................................     2
                  Affiliate; control......................................................................     2
                  Authenticating Agent....................................................................     2
                  Board of Directors......................................................................     2
                  Board Resolution........................................................................     2
                  Business Day............................................................................     2
                  Commission..............................................................................     2
                  Common Stock............................................................................     2
                  Company.................................................................................     3
                  Company Request; Company Order..........................................................     3
                  Corporate Trust Office..................................................................     3
                  Corporation.............................................................................     3
                  Covenant Defeasance.....................................................................     3
                  Debt....................................................................................     3
                  Defaulted Interest......................................................................     3
                  Defeasance..............................................................................     3
                  Depositary..............................................................................     3
                  Event of Default........................................................................     3
                  Exchange Act............................................................................     3
                  Expiration Date.........................................................................     3
                  Global Security.........................................................................     3
                  Holder..................................................................................     3
                  Indenture...............................................................................     3
                  Interest................................................................................     4
                  Interest Payment Date...................................................................     4
                  Investment Company Act..................................................................     4
                  Lien....................................................................................     4
                  Maturity................................................................................     4
                  Notice of Default.......................................................................     4
                  Officers' Certificate...................................................................     4
                  Opinion of Counsel......................................................................     4
                  Original Issue Discount Security........................................................     4
 

 
 
 
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                  Outstanding.............................................................................     4
                  Paying Agent............................................................................     5
                  Person..................................................................................     5
                  Place of Payment........................................................................     5
                  Predecessor Security....................................................................     5
                  Redemption Date.........................................................................     5
                  Redemption Price........................................................................     6
                  Regular Record Date.....................................................................     6
                  Securities..............................................................................     6
                  Securities Act..........................................................................     6
                  Security Register and Security Registrar................................................     6
                  Senior Debt.............................................................................     6
                  Special Record Date.....................................................................     6
                  Stated Maturity.........................................................................     6
                  Subsidiary..............................................................................     6
                  Trust Indenture Act.....................................................................     6
                  Trustee.................................................................................     6
                  U.S. Government Obligation..............................................................     7
                  Vice President..........................................................................     7
Section 102.      Compliance Certificates and Opinions....................................................     7
Section 103.      Form of Documents Delivered to Trustee..................................................     7
Section 104.      Acts of Holders; Record Dates...........................................................     8
Section 105.      Notices, Etc., to Trustee and Company...................................................    10
Section 106.      Notice to Holders; Waiver...............................................................    10
Section 107.      Conflict with Trust Indenture Act.......................................................    10
Section 108.      Effect of Headings and Table of Contents................................................    10
Section 109.      Successors and Assigns..................................................................    11
Section 110.      Separability Clause.....................................................................    11
Section 111.      Benefits of Indenture...................................................................    11
Section 112.      Governing Law...........................................................................    11
Section 113.      Legal Holidays..........................................................................    11

                                                            ARTICLE TWO

                                                          Security Forms

Section 201.      Forms Generally.........................................................................    11
Section 202.      Form of Face of Security................................................................    12
Section 203.      Form of Reverse of Security.............................................................    13
Section 204.      Form of Legend for Global Securities....................................................    18
Section 205.      Form of Trustee's Certificate of Authentication.........................................    18
 

                                     -ii-

 
 
 
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Section 206.      Form of Conversion Notice...............................................................    18

                                                           ARTICLE THREE

                                                          The Securities

Section 301.      Amount Unlimited; Issuable in Series....................................................    19
Section 302.      Denominations...........................................................................    22
Section 303.      Execution, Authentication, Delivery and Dating..........................................    22
Section 304.      Temporary Securities....................................................................    23
Section 305.      Registration, Registration of Transfer and Exchange.....................................    24
Section 306.      Mutilated, Destroyed, Lost and Stolen Securities........................................    25
Section 307.      Payment of Interest; Interest Rights Preserved..........................................    26
Section 308.      Persons Deemed Owners...................................................................    27
Section 309.      Cancellation............................................................................    28
Section 310.      Computation of Interest.................................................................    28

                                                           ARTICLE FOUR

                                                    Satisfaction and Discharge

Section 401.      Satisfaction and Discharge of Indenture.................................................    28
Section 402.      Application of Trust Money..............................................................    29

                                                           ARTICLE FIVE

                                                             Remedies

Section 501.      Events of Default.......................................................................    29
Section 502.      Acceleration of Maturity; Rescission and Annulment......................................    31
Section 503.      Collection of Indebtedness and Suits for
                     Enforcement by Trustee...............................................................    32
Section 504.      Trustee May File Proofs of Claim........................................................    32
Section 505.      Trustee May Enforce Claims Without Possession
                     of Securities........................................................................    33
Section 506.      Application of Money Collected..........................................................    33
Section 507.      Limitation on Suits.....................................................................    33
Section 508.      Unconditional Right of Holders to Receive Principal,
                     Premium and Interest and to Convert..................................................    34
Section 509.      Restoration of Rights and Remedies......................................................    34
 

                                     -iii-

 
 
 
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Section 510.      Rights and Remedies Cumulative..........................................................    34
Section 511.      Delay or Omission Not Waiver............................................................    34
Section 512.      Control by Holders......................................................................    35
Section 513.      Waiver of Past Defaults.................................................................    35
Section 514.      Undertaking for Costs...................................................................    35
Section 515.      Waiver of Usury, Stay or Extension Laws.................................................    35

                                                            ARTICLE SIX

                                                            The Trustee

Section 601.      Certain Duties and Responsibilities.....................................................    36
Section 602.      Notice of Defaults......................................................................    36
Section 603.      Certain Rights of Trustee...............................................................    36
Section 604.      Not Responsible for Recitals or Issuance of Securities..................................    37
Section 605.      May Hold Securities.....................................................................    37
Section 606.      Money Held in Trust.....................................................................    37
Section 607.      Compensation and Reimbursement..........................................................    38
Section 608.      Conflicting Interests...................................................................    38
Section 609.      Corporate Trustee Required; Eligibility.................................................    38
Section 610.      Resignation and Removal; Appointment of Successor.......................................    39
Section 611.      Acceptance of Appointment by Successor..................................................    40
Section 612.      Merger, Conversion, Consolidation or Succession
                     to Business..........................................................................    41
Section 613.      Preferential Collection of Claims Against Company.......................................    41
Section 614.      Appointment of Authenticating Agent.....................................................    41

                                                           ARTICLE SEVEN

                                         Holders' Lists and Reports by Trustee and Company

Section 701.      Company to Furnish Trustee Names and Addresses
                     of Holders...........................................................................    43
Section 702.      Preservation of Information; Communications
                     to Holders...........................................................................    43
Section 703.      Reports by Trustee......................................................................    43
Section 704.      Reports by Company......................................................................    44
 

                                     -iv-

 
 
 
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                                                           ARTICLE EIGHT

                                       Consolidation, Merger, Conveyance, Transfer or Lease

Section 801.      Company May Consolidate, Etc., Only on
                     Certain Terms........................................................................    44
Section 802.      Successor Substituted...................................................................    45

                                                           ARTICLE NINE

                                                      Supplemental Indentures

Section 901.      Supplemental Indentures Without Consent of Holders......................................    45
Section 902.      Supplemental Indentures With Consent of Holders.........................................    46
Section 903.      Execution of Supplemental Indentures....................................................    47
Section 904.      Effect of Supplemental Indentures.......................................................    48
Section 905.      Conformity with Trust Indenture Act.....................................................    48
Section 906.      Reference in Securities to Supplemental Indentures......................................    48
Section 907.      Subordination Unimparied................................................................    48

                                                            ARTICLE TEN

                                                             Covenants

Section 1001.     Payment of Principal, Premium and Interest..............................................    48
Section 1002.     Maintenance of Office or Agency.........................................................    48
Section 1003.     Money for Securities Payments to Be Held in Trust.......................................    49
Section 1004.     Statement by Officers as to Default.....................................................    50
Section 1005.     Existence...............................................................................    50
Section 1006.     Maintenance of Properties...............................................................    50
Section 1007.     Payment of Taxes and Other Claims.......................................................    50
Section 1008.     Waiver of Certain Covenants.............................................................    51

                                                          ARTICLE ELEVEN

                                                     Redemption of Securities

Section 1101.     Applicability of Article................................................................    51
Section 1102.     Election to Redeem; Notice to Trustee...................................................    51
Section 1103.     Selection by Trustee of Securities to Be Redeemed.......................................    51
Section 1104.     Notice of Redemption....................................................................    52
 

                                      -v-

 
 
 
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Section 1105.     Deposit of Redemption Price.............................................................    53
Section 1106.     Securities Payable on Redemption Date...................................................    53
Section 1107.     Securities Redeemed in Part.............................................................    53

                                                          ARTICLE TWELVE

                                                           Sinking Funds

Section 1201.     Applicability of Article................................................................    54
Section 1202.     Satisfaction of Sinking Fund Payments with Securities...................................    54
Section 1203.     Redemption of Securities for Sinking Fund...............................................    54

                                                         ARTICLE THIRTEEN

                                                Defeasance and Covenant Defeasance

Section 1301.     Company's Option to Effect Defeasance or
                     Covenant Defeasance..................................................................    55
Section 1302.     Defeasance and Discharge................................................................    55
Section 1303.     Covenant Defeasance.....................................................................    55
Section 1304.     Conditions to Defeasance or Covenant Defeasance.........................................    56
Section 1305.     Deposited Money and U.S. Government Obligations
                     to Be Held in Trust; Miscellaneous Provisions........................................    58
Section 1306.     Reinstatement...........................................................................    58

                                                         ARTICLE FOURTEEN

                                                     Conversion of Securities

Section 1401.     Applicability of Article................................................................    59
Section 1402.     Exercise of Conversion Privilege........................................................    59
Section 1403.     No Fractional Shares....................................................................    60
Section 1404.     Adjustment of Conversion Price..........................................................    60
Section 1405.     Notice of Certain Corporate Actions.....................................................    61
Section 1406.     Reservation of Shares of Common Stock...................................................    61
Section 1407.     Payment of Certain Taxes Upon Conversion................................................    62
Section 1408.     Nonassessability........................................................................    62
Section 1409.     Effect of Consolidation or Merger on Conversion Privilege...............................    62
Section 1410.     Duties of Trustee Regarding Conversion..................................................    63
Section 1411.     Repayment of Certain Funds Upon Conversion..............................................    63
 

                                     -vi-

 
 
 
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                                                          ARTICLE FIFTEEN

                                                    Subordination of Securities

Section 1501.     Securities Subordinate to Senior Debt...................................................    64
Section 1502.     Payment Over of Proceeds Upon Dissolution, Etc..........................................    64
Section 1503.     Prior Payment to Senior Debt Upon Acceleration
                     of Securities........................................................................    65
Section 1504.     No Payment When Senior Debt in Default..................................................    65
Section 1505.     Payment Permitted If No Default.........................................................    66
Section 1506.     Subrogation to Rights of Holders of Senior Debt.........................................    66
Section 1507.     Provisions Solely to Define Relative Rights.............................................    66
Section 1508.     Trustee to Effectuate Subordination.....................................................    67
Section 1509.     No Waiver of Subordination Provisions...................................................    67
Section 1510.     Notice to Trustee.......................................................................    67
Section 1511.     Reliance on Judicial Order or Certificate of
                     Liquidating Agent....................................................................    68
Section 1512.     Trustee Not Fiduciary for Holders of Senior Debt........................................    68
Section 1513.     Rights of Trustee as Holder of Senior Debt;
                     Preservation of Trustee's Rights.....................................................    68
Section 1514.     Article Applicable to Paying Agents.....................................................    69
Section 1515.     Certain Conversions Deemed Payment......................................................    69
Section 1516.     Obligations of Company and Right to Convert
                     Unconditional........................................................................    69

Testimonium...............................................................................................    70
Signatures and Seals......................................................................................    70
Acknowledgements..........................................................................................    71
 

                                     -vii-

 
                    --------------------------------------
          Certain Sections of this Indenture relating to Sections 310
          through 318, inclusive, of the Trust Indenture Act of 1939:

 
 
  Trust Indenture
    Act Section                                                                              Indenture Section
                                                                                           
(s) 310 (a) (1)      ...................................................................     609
        (a) (2)      ...................................................................     609
        (a) (3)      ...................................................................     Not Applicable
        (a) (4)      ...................................................................     Not Applicable
        (b)          ...................................................................     608, 610
(s) 311 (a)          ...................................................................     613
        (b)          ...................................................................     613
(s) 312 (a)          ...................................................................     701, 702
        (b)          ...................................................................     702
        (c)          ...................................................................     702
(s) 313 (a)          ...................................................................     703
        (b)          ...................................................................     703
        (c)          ...................................................................     703
        (d)          ...................................................................     703
(s) 314 (a)          ...................................................................     704
        (a) (4)      ...................................................................     101, 1004
        (b)          ...................................................................     Not Applicable
        (c) (1)      ...................................................................     102
        (c) (2)      ...................................................................     102
        (c) (3)      ...................................................................     Not Applicable
        (d)          ...................................................................     Not Applicable
        (e)          ...................................................................     102
(s) 315 (a)          ...................................................................     601
        (b)          ...................................................................     602
        (c)          ...................................................................     601
        (d)          ...................................................................     601
        (e)          ...................................................................     514
(s) 316 (a)          ...................................................................     101
        (a) (1) (A)  ...................................................................     502, 512
        (a) (1) (B)  ...................................................................     513
        (a) (2)      ...................................................................     Not Applicable
        (b)          ...................................................................     508
        (c)          ...................................................................     104
(s) 317 (a) (1)      ...................................................................     503
        (a) (2)      ...................................................................     504
        (b)          ...................................................................     1003
(s) 318 (a)          ...................................................................     107
 

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

                                    -viii-

 
     INDENTURE, dated as of December 23, 1998, between Armstrong World
Industries, Inc., a corporation duly organized and existing under the laws of
the Commonwealth of Pennsylvania (herein called the "Company"), having its
principal executive office at 2500 Columbia Avenue, Lancaster, Pennsylvania
17603, and The First National Bank of Chicago, a national banking association
duly organized and existing under the laws of the United States of America, as
Trustee (herein called the "Trustee").

                            Recitals of the Company

     The Company has duly authorized the execution and delivery of this
Indenture to provide for the issuance from time to time of its unsecured
debentures, notes or other evidences of indebtedness (herein called the
"Securities"), to be issued in one or more series as in this Indenture provided.

     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 agreed, for the equal and proportionate
benefit of all Holders of the Securities or of 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 Trust
     Indenture Act, either directly or by reference therein, have the meanings
     assigned to them therein;

          (3)  all accounting terms not otherwise defined herein have the
     meanings assigned to them in accordance with generally accepted accounting
     principles, and, except as otherwise herein expressly provided, the term
     "generally accepted accounting principles" with respect to any computation
     required or permitted hereunder shall mean such accounting principles as
     are generally accepted at the date of such computation;

          (4)  unless the context otherwise requires, any reference to an
     "Article" or a "Section" refers to an Article or a Section, as the case may
     be, of this Indenture; and

 
          (5)  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.

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

     "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 Person authorized by the Trustee pursuant
to Section 614 to act on behalf of the Trustee to authenticate Securities of one
or more series.

     "Board of Directors" means either the board of directors of the Company or
any duly authorized committee of that board.

     "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
of Directors 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, means each
Monday, Tuesday, Wednesday, Thursday and Friday which is not a day on which
banking institutions in that Place of Payment are authorized or obligated by law
or executive order to close.

     "Commission" means the Securities and Exchange Commission, from time to
time constituted, created under the Exchange Act, or, if at any time after the
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 at such time.

     "Common Stock" includes any stock of any class of the Company which has no
preference in respect of dividends or of amounts payable in the event of any
voluntary or involuntary liquidation, dissolution or winding-up of the Company
and which is not subject to redemption by the Company. However, subject to the
provisions of Section 1409, shares issuable on conversions of Securities shall
include only shares of the class designated as Common Stock of the Company at
the date of this Indenture or shares of any class or classes resulting from any
reclassification or reclassifications thereof and which have no preference in
respect of dividends or of amounts payable in the event of any voluntary or
involuntary liquidation, dissolution or winding-up of the Company and which are
not subject to redemption by the Company; provided that if at any time there
shall be more than one such resulting class, the shares of each such class then
so issuable shall be substantially in the proportion which the total number of
shares of such class resulting from all such reclassifications bears to the
total number of shares of all such classes resulting from all such
reclassifications.

                                      -2-

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

     "Company Request" or "Company Order" means a written request or order
signed in the name of the Company by its Chairman of the Board, its Vice
Chairman of the Board, its President or a Vice President, and by its Treasurer,
an Assistant Treasurer, its Secretary or an Assistant Secretary, and delivered
to the Trustee.

     "Corporate Trust Office" means the corporate trust office of the Trustee at
The First National Bank of Chicago, One First National Plaza, Suite 0126,
Chicago, Illinois, 60670-0126 at which at any particular time its corporate
trust business shall be administered.

     "Corporation" means a corporation, association, company, joint-stock
company or business trust.

     "Covenant Defeasance" has the meaning specified in Section 1303.

     "Debt" means indebtedness for borrowed money.

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

     "Defeasance" has the meaning specified in Section 1302.

     "Depositary" means, with respect to Securities of any series issuable in
whole or in part in the form of one or more Global Securities, a clearing agency
registered under the Exchange Act that is designated to act as Depositary for
such Securities as contemplated by Section 301.

     "Event of Default" has the meaning specified in Section 501.

     "Exchange Act" means the Securities Exchange Act of 1934 and any statute
successor thereto, in each case as amended from time to time.

     "Expiration Date" has the meaning specified in Section 104.

     "Global Security" means a Security that evidences all or part of the
Securities of any series and bears the legend set forth in Section 204 (or such
legend as may be specified as contemplated by Section 301 for such Securities).

     "Holder" means a Person in whose name a Security is registered in the
Security Register.

     "Indenture" means this instrument as originally executed and 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, including, for
all purposes of this instrument and any such supplemental indenture, the
provisions of the Trust Indenture Act that are deemed to be a part of and govern
this instrument and any such supplemental indenture, respectively. The term
"Indenture" shall also include the terms of particular series of Securities
established as contemplated by Section 301.

                                      -3-

 
     "Interest", when used with respect to an Original Issue Discount Security
which by its terms bears interest only after Maturity, means interest payable
after Maturity.

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

     "Investment Company Act" means the Investment Company Act of 1940 and any
statute successor thereto, in each case as amended from time to time.

     "Lien" means any mortgage, pledge, security interest, lien or other
encumbrance.

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

     "Notice of Default" means a written notice of the kind specified in Section
501(4) or 501(5).

     "Officers' Certificate" means a certificate signed by the Chairman of the
Board, a Vice Chairman of the Board, the President or a Vice President, and by
the Treasurer, an Assistant Treasurer, the Secretary or an Assistant Secretary,
of the Company, and delivered to the Trustee. One of the officers signing an
Officers' Certificate given pursuant to Section 1004 shall be the principal
executive, financial or accounting officer of the Company.

     "Opinion of Counsel" means a written opinion of counsel, who may be counsel
for 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:

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

          (2)  Securities for whose payment or redemption 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; 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;

          (3)  Securities as to which Defeasance has been effected pursuant to
     Section 1302; and

                                      -4-

 
          (4)  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;

provided, however, that in determining whether the Holders of the requisite
principal amount of the Outstanding Securities have given, made or taken any
request, demand, authorization, direction, notice, consent, waiver or other
action hereunder as of any date, (A) the principal amount of an Original Issue
Discount Security which shall be deemed to be Outstanding shall be the amount of
the principal thereof which would be due and payable as of such date upon
acceleration of the Maturity thereof to such date pursuant to Section 502, (B)
if, as of such date, the principal amount payable at the Stated Maturity of a
Security is not determinable, the principal amount of such Security which shall
be deemed to be Outstanding shall be the amount as specified or determined as
contemplated by Section 301, (C) the principal amount of a Security denominated
in one or more foreign currencies or currency units which shall be deemed to be
Outstanding shall be the U.S. dollar equivalent, determined as of such date in
the manner provided as contemplated by Section 301, of the principal amount of
such Security (or, in the case of a Security described in Clause (A) or (B)
above, of the amount determined as provided in such Clause), and (D) 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 relying upon any such request, demand, authorization, direction,
notice, consent, waiver or other action, 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 or any premium or interest on any Securities on behalf of the
Company.

     "Person" means any individual, corporation, partnership, joint venture,
trust, unincorporated organization or government or any agency or political
subdivision thereof.

     "Place of Payment", when used with respect to the Securities of any series,
means the place or places where the principal of and any premium and interest on
the Securities of that series are payable as specified as contemplated by
Section 301.

     "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 shall be deemed to evidence the
same debt as the mutilated, destroyed, lost or stolen Security.

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

                                      -5-

 
     "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.

     "Regular Record Date" for the interest payable on any Interest Payment Date
on the Securities of any series means the date specified for that purpose as
contemplated by Section 301.

     "Securities" has the meaning stated in the first recital of this Indenture
and more particularly means any Securities authenticated and delivered under
this Indenture.

     "Securities Act" means the Securities Act of 1933 and any statute successor
thereto, in each case as amended from time to time.

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

     "Senior Debt" means the principal of (and premium, if any) and interest, if
any, (including interest accruing on or after the filing of any petition in
bankruptcy or for reorganization relating to the Company to the extent that such
claim for post-petition interest is allowed in such proceeding) on Debt, whether
incurred on or prior to the date hereof or hereafter incurred, unless, in the
instrument creating or evidencing the same or pursuant to which the same is
outstanding, it is provided that such obligations are not superior in right of
payment to the Securities or to other Debt which is pari passu with, or
subordinated to, the Securities; provided, however, that Senior Debt shall not
be deemed to include the Securities.

     "Special Record Date" for the payment of any Defaulted Interest 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 as the fixed date on which the principal of such Security or
such instalment of principal or interest is due and payable.

     "Subsidiary" means a corporation more than 50% of the outstanding voting
stock of which is owned, directly or indirectly, by the Company or by one or
more other Subsidiaries, or by the Company and one or more other Subsidiaries.
For the purposes of this definition, "voting stock" means stock which ordinarily
has 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" means the Trust Indenture Act of 1939 as in force at
the date as of which this instrument was executed; provided, however, that in
the event the Trust Indenture Act of 1939 is amended after such date, "Trust
Indenture Act" means, to the extent required by any such amendment, the Trust
Indenture Act of 1939 as so amended.

     "Trustee" means the Person named as the "Trustee" in the first paragraph of
this instrument 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, and if at any time there is
more than one such Person, "Trustee" as used with respect to the Securities of
any series shall mean the Trustee with respect to Securities of that series.

                                      -6-

 
     "U.S. Government Obligation" has the meaning specified in Section 1304.

     "Vice President", when used with respect to the Company or the Trustee,
means any vice president, whether or not designated by a number or a word or
words added before or after the title "vice president".

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 such certificates and opinions as may be required under the Trust
Indenture Act. Each such certificate or opinion shall be given in the form of an
Officers' Certificate, if to be given by an officer of the Company, or an
Opinion of Counsel, if to be given by counsel, and shall comply with the
requirements of the Trust Indenture Act and any other requirements set forth in
this Indenture.

     Every certificate or opinion with respect to compliance with a condition or
covenant provided for in this Indenture shall include,

          (1)  a statement that each individual signing such certificate or
     opinion has read such covenant or condition 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 or
     she has made such examination or investigation as is necessary to enable
     him or her to express an informed opinion as to whether or not such
     covenant or condition 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 with respect 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 a certificate or opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to the matters upon which his or her certificate or opinion is
based are erroneous. Any such certificate or opinion of counsel 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 stating that the
information 

                                      -7-

 
with respect to such factual matters is in the possession of the Company, unless
such counsel knows, or in the exercise of reasonable care should know, that the
certificate or opinion or representations with respect 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; Record Dates.

     Any request, demand, authorization, direction, notice, consent, waiver or
other action provided or permitted by this Indenture to be given, made or taken
by Holders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by agent duly
appointed in writing; and, except as herein otherwise expressly provided, such
action shall become effective when such instrument or instruments are delivered
to the Trustee and, where it is hereby expressly required, to the Company. Such
instrument or instruments (and the action embodied therein and evidenced
thereby) are herein sometimes referred to as the "Act" of the Holders signing
such instrument or instruments. Proof of execution of any such instrument or of
a writing appointing any such agent shall be sufficient for any purpose of this
Indenture and (subject to Section 601) conclusive in favor of the Trustee and
the Company, if made in the manner provided in this Section.

     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 or her the execution thereof. Where such
execution is by a signer acting in a capacity other than his or her individual
capacity, such certificate or affidavit shall also constitute sufficient proof
of his or her 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 manner which the Trustee deems sufficient.

     The ownership of Securities shall be proved by the Security Register.

     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 or the Company in
reliance thereon, whether or not notation of such action is made upon such
Security.

     The Company may set any day as a record date for the purpose of determining
the Holders of Outstanding Securities of any series entitled to give, make or
take any request, demand, authorization, direction, notice, consent, waiver or
other action provided or permitted by this Indenture to be given, made or taken
by Holders of Securities of such series, provided that the Company may not set a
record date for, and the provisions of this paragraph shall not apply with
respect to, the giving or making of any notice, declaration, request or
direction referred to in the next paragraph. If any record date is set pursuant
to this paragraph, the Holders of Outstanding Securities of the relevant series
on such record date, and no other Holders, shall be entitled to take the
relevant action, whether or not such Holders remain Holders after such record
date; provided that no such action shall be effective hereunder unless 

                                      -8-

 
taken on or prior to the applicable Expiration Date by Holders of the requisite
principal amount of Outstanding Securities of such series on such record date.
Nothing in this paragraph shall be construed to prevent the Company from setting
a new record date for any action for which a record date has previously been set
pursuant to this paragraph (whereupon the record date previously set shall
automatically and with no action by any Person be cancelled and of no effect),
and nothing in this paragraph shall be construed to render ineffective any
action taken by Holders of the requisite principal amount of Outstanding
Securities of the relevant series on the date such action is taken. Promptly
after any record date is set pursuant to this paragraph, the Company, at its own
expense, shall cause notice of such record date, the proposed action by Holders
and the applicable Expiration Date to be given to the Trustee in writing and to
each Holder of Securities of the relevant series in the manner set forth in
Section 106.

     The Trustee may set any day as a record date for the purpose of determining
the Holders of Outstanding Securities of any series entitled to join in the
giving or making of (i) any Notice of Default, (ii) any declaration of
acceleration referred to in Section 502, (iii) any request to institute
proceedings referred to in Section 507(2) or (iv) any direction referred to in
Section 512, in each case with respect to Securities of such series. If any
record date is set pursuant to this paragraph, the Holders of Outstanding
Securities of such series on such record date, and no other Holders, shall be
entitled to join in such notice, declaration, request or direction, whether or
not such Holders remain Holders after such record date; provided that no such
action shall be effective hereunder unless taken on or prior to the applicable
Expiration Date by Holders of the requisite principal amount of Outstanding
Securities of such series on such record date. Nothing in this paragraph shall
be construed to prevent the Trustee from setting a new record date for any
action for which a record date has previously been set pursuant to this
paragraph (whereupon the record date previously set shall automatically and with
no action by any Person be cancelled and of no effect), and nothing in this
paragraph shall be construed to render ineffective any action taken by Holders
of the requisite principal amount of Outstanding Securities of the relevant
series on the date such action is taken. Promptly after any record date is set
pursuant to this paragraph, the Trustee, at the Company's expense, shall cause
notice of such record date, the proposed action by Holders and the applicable
Expiration Date to be given to the Company in writing and to each Holder of
Securities of the relevant series in the manner set forth in Section 106.

     With respect to any record date set pursuant to this Section, the party
hereto which sets such record dates may designate any day as the "Expiration
Date" and from time to time may change the Expiration Date to any earlier or
later day; provided that no such change shall be effective unless notice of the
proposed new Expiration Date is given to the other party hereto in writing, and
to each Holder of Securities of the relevant series in the manner set forth in
Section 106, on or prior to the existing Expiration Date. If an Expiration Date
is not designated with respect to any record date set pursuant to this Section,
the party hereto which set such record date shall be deemed to have initially
designated the 180th day after such record date as the Expiration Date with
respect thereto, subject to its right to change the Expiration Date as provided
in this paragraph. Notwithstanding the foregoing, no Expiration Date shall be
later than the 180th day after the applicable record date.

     Without limiting the foregoing, a Holder entitled hereunder to take any
action hereunder with regard to any particular Security may do so with regard to
all or any part of the principal amount of such Security or by one or more duly
appointed agents each of which may do so pursuant to such appointment with
regard to all or any part of such principal amount.

                                      -9-

 
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,

          (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: Corporate
     Trust Administration, 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 instrument or at any other address previously
     furnished in writing to the Trustee by the Company, Attention: Chief
     Financial Officer.

Section 106.  Notice to Holders; Waiver.

     Where this Indenture provides for notice to Holders of any event, such
notice shall be sufficiently given (unless otherwise herein expressly provided)
if in writing and mailed, first-class postage prepaid, to each Holder affected
by such event, at its address as it appears in the Security Register, not later
than the latest date (if any), and not earlier than the earliest date (if any),
prescribed for the giving of such notice. In any case where notice to Holders 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. 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.

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


Section 107.  Conflict with Trust Indenture Act.

     If any provision hereof limits, qualifies or conflicts with a provision of
the Trust Indenture Act which is required under such Act to be a part of and
govern this Indenture, the latter provision shall control. If any provision of
this Indenture modifies or excludes any provision of the Trust Indenture Act
which may be so modified or excluded, the latter provision shall be deemed to
apply to this Indenture as so modified or to be excluded, as the case may be.

Section 108.  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 109.  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 110.  Separability Clause.

     In case any provision in this Indenture or in the Securities 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 111.  Benefits of Indenture.

     Nothing in this Indenture or in the Securities, express or implied, shall
give to any Person, other than the parties hereto and their successors
hereunder, the holders of Senior Debt and the Holders, any benefit or any legal
or equitable right, remedy or claim under this Indenture.

Section 112.  Governing Law.

     This Indenture and the Securities shall be governed by and construed in
accordance with the law of the State of New York.

Section 113.  Legal Holidays.

     In any case where any Interest Payment Date, Redemption Date or Stated
Maturity of any Security or the last date on which a Holder has the right to
convert a Security at a particular conversion price shall not be a Business Day
at any Place of Payment, then (notwithstanding any other provision of this
Indenture or of the Securities (other than a provision of any Security which
specifically states that such provision shall apply in lieu of this Section))
payment of interest or principal (and premium, if any) or, if applicable to a
particular series of Securities, conversion 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 or Redemption Date, at the Stated Maturity or on such last day for
conversion.

                                  ARTICLE TWO

                                Security Forms

Section 201.  Forms Generally.

     The Securities of each series shall be in substantially the form set forth
in this Article, or in such other form as shall be established by or pursuant to
a Board Resolution or in one or more indentures supplemental hereto, in each
case with such appropriate insertions, omissions, substitutions and other
variations as are required or permitted by this Indenture, and may have such
letters, numbers or other marks of identification and such legends or
endorsements placed thereon as may be required to comply with the rules of any
securities exchange or Depositary therefor or as may, consistently 

                                      -11-

 
herewith, be determined by the officers executing such Securities, as evidenced
by their execution thereof. If the form of Securities of any series is
established by action taken pursuant to a Board Resolution, a copy of an
appropriate record of such action 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 Company Order contemplated by Section 303 for the
authentication and delivery of such Securities. Any such Board Resolution or
record of such action shall have attached thereto a true and correct copy of the
form of Security referred to therein approved by or pursuant to such Board
Resolution.

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

Section 202.  Form of Face of Security.

          ___________________________________________________________

________________________________________________________________________________

No. _________                                                        $ _________

     Armstrong World Industries, Inc., a corporation duly organized and existing
under the laws of Pennsylvania (herein called the "Company", which term includes
any successor Person under the Indenture hereinafter referred to), for value
received, hereby promises to pay to __________________, or registered assigns,
the principal sum of ____________________ Dollars on __________________ [if the
Security is to bear interest prior to Maturity, insert -- , and to pay interest
thereon from _______ or from the most recent Interest Payment Date to which
interest has been paid or duly provided for, semi-annually on _______ and
_______ in each year, commencing _______, at the rate of ___% per annum, until
the principal hereof is paid or made available for payment [if applicable,
insert -- , provided that any principal and premium, and any such instalment of
interest, which is overdue shall bear interest at the rate of ____% per annum
(to the extent that the payment of such interest shall be legally enforceable),
from the dates such amounts are due until they are paid or made available for
payment, and such interest shall be payable on demand]. The interest so payable,
and punctually paid or duly provided for, on any Interest Payment Date will, as
provided in such Indenture, be paid to the Person in whose name this Security
(or one or more Predecessor Securities) is registered at the close of business
on the Regular Record Date for such interest, which shall be the _____ or _____
(whether or not a Business Day), as the case may be, next preceding such
Interest Payment Date. Any such interest not so punctually paid or duly provided
for will forthwith cease to be payable to the Holder on such Regular Record Date
and may either be paid to the Person in whose name this Security (or one or more
Predecessor Securities) is registered at the close of business on a Special
Record Date for the payment of such Defaulted Interest to be fixed by the
Trustee, notice whereof shall be given to Holders of Securities of this series
not less than 10 days prior to such Special Record Date, or be paid at any time
in any other lawful manner not inconsistent with the requirements of any
securities exchange on which the Securities of this series may be listed, and
upon such notice as may be required by such exchange, all as more fully provided
in said Indenture].

     [If the Security is not to bear interest prior to Maturity, insert -- The
principal of this Security shall not bear interest except in the case of a
default in payment of principal upon acceleration, upon 

                                      -12-

 
redemption or at Stated Maturity and in such case the overdue principal and any
overdue premium shall bear interest at the rate of ____% per annum (to the
extent that the payment of such interest shall be legally enforceable), from the
dates such amounts are due until they are paid or made available for payment.
Interest on any overdue principal or premium shall be payable on demand. [Any
such interest on overdue principal or premium which is not paid on demand shall
bear interest at the rate of ____% per annum (to the extent that the payment of
such interest on interest shall be legally enforceable), from the date of such
demand until the amount so demanded is paid or made available for payment.
Interest on any overdue interest shall be payable on demand.]]

     Payment of the principal of (and premium, if any) and [if applicable,
insert -- any such] interest on this Security will be made at the office or
agency of the Company maintained for that purpose in ________, in such coin or
currency of the United States of America as at the time of payment is legal
tender for payment of public and private debts [if applicable, insert -- ;
provided, however, that at the option of the Company payment of interest may be
made by check mailed to the address of the Person entitled thereto as such
address shall appear in the Security Register].

     Reference is hereby made to the further provisions of this Security set
forth on the reverse hereof, which further provisions shall for all purposes
have the same effect as if set forth at this place.

     Unless the certificate of authentication hereon has been executed by the
Trustee referred to on the reverse hereof by manual signature, this Security
shall not be entitled to any benefit under the Indenture or be valid or
obligatory for any purpose.

     In Witness Whereof, the Company has caused this instrument to be duly
executed under its corporate seal.

Dated:

                      __________________________________________________________

                      By _______________________________________________________

Attest:

_______________________________________

Section 203.  Form of Reverse of Security.

     This Security is one of a duly authorized issue of securities of the
Company (herein called the "Securities"), issued and to be issued in one or more
series under an Indenture, dated as of December 23, 1998 (herein called the
"Indenture", which term shall have the meaning assigned to it in such
instrument), between the Company and The First National Bank of Chicago, as
Trustee (herein called the "Trustee", which term includes any successor trustee
under the Indenture), and reference is hereby made to the Indenture and all
indentures supplemental thereto for a statement of the respective rights,
limitations of rights, duties and immunities thereunder of the Company, the
Trustee, the holders of Senior Debt and the Holders of the Securities and of the
terms upon which the Securities are, and are to 

                                      -13-

 
be, authenticated and delivered. This Security is one of the series designated
on the face hereof [if applicable, insert -- , limited in aggregate principal
amount to $______].

     [If applicable, insert -- The Securities of this series are subject to
redemption upon not less than 30 days' notice by mail, [if applicable, insert --
(1) on ______ in any year commencing with the year ______ and ending with the
year ______ through operation of the sinking fund for this series at a
Redemption Price equal to 100% of the principal amount, and (2)] at any time [if
applicable, insert -- on or after ______, 19__], as a whole or in part, at the
election of the Company, at the following Redemption Prices (expressed as
percentages of the principal amount): If redeemed [if applicable, insert -- on
or before _________, __%, and if redeemed] during the 12-month period beginning
________ of the years indicated,

                Redemption                           Redemption
  Year            Price                Year             Price
  ----          -----------            ----         ------------



and thereafter at a Redemption Price equal to ____% of the principal amount,
together in the case of any such redemption [if applicable, insert -- (whether
through operation of the sinking fund or otherwise)] with accrued interest to
the Redemption Date, but interest instalments whose Stated Maturity is on or
prior to such Redemption Date will be payable to the Holders of such Securities,
or one or more Predecessor Securities, of record at the close of business on the
relevant Record Dates referred to on the face hereof, all as provided in the
Indenture.]

     [If applicable, insert -- The Securities of this series are subject to
redemption upon not less than 30 days' notice by mail, (1) on _________ in any
year commencing with the year ____ and ending with the year ____ through
operation of the sinking fund for this series at the Redemption Prices for
redemption through operation of the sinking fund (expressed as percentages of
the principal amount) set forth in the table below, and (2) at any time [if
applicable, insert -- on or after ________], as a whole or in part, at the
election of the Company, at the Redemption Prices for redemption otherwise than
through operation of the sinking fund (expressed as percentages of the principal
amount) set forth in the table below: If redeemed during the 12-month period
beginning _________ of the years indicated,

                     Redemption Price
                      For Redemption          Redemption Price For
                     Through Operation        Redemption Otherwise
                         of the              Than Through Operation
  Year                Sinking Fund             of the Sinking Fund
  ----              -------------------     -----------------------



and thereafter at a Redemption Price equal to ___% of the principal amount,
together in the case of any such redemption (whether through operation of the
sinking fund or otherwise) with accrued interest to the Redemption Date, but
interest instalments whose Stated Maturity is on or prior to such Redemption
Date will be payable to the Holders of such Securities, or one or more
Predecessor Securities, of record 

                                      -14-

 
at the close of business on the relevant Record Dates referred to on the face
hereof, all as provided in the Indenture.]

     [If applicable, insert -- Notwithstanding the foregoing, the Company may
not, prior to ______, redeem any Securities of this series as contemplated by
[if applicable, insert -- Clause (2) of] the preceding paragraph as a part of,
or in anticipation of, any refunding operation by the application, directly or
indirectly, of moneys borrowed having an interest cost to the Company
(calculated in accordance with generally accepted financial practice) of less
than _____% per annum.]

     [If applicable, insert -- The sinking fund for this series provides for the
redemption on ______ in each year beginning with the year _____ and ending with
the year ____ of [if applicable, insert -- not less than $______ ("mandatory
sinking fund") and not more than] $______ aggregate principal amount of
Securities of this series. Securities of this series acquired or redeemed by the
Company otherwise than through [if applicable, insert -- mandatory] sinking fund
payments may be credited against subsequent [if applicable, insert -- mandatory]
sinking fund payments otherwise required to be made [if applicable, insert -- ,
in the inverse order in which they become due].]

     [If the Security is subject to redemption of any kind, insert -- In the
event of redemption of this Security in part only, a new Security or Securities
of this series and of like tenor for the unredeemed portion hereof will be
issued in the name of the Holder hereof upon the cancellation hereof.]

     [If applicable, insert -- The Indenture contains provisions for defeasance
at any time of [the entire indebtedness of this Security] [or] [certain
restrictive covenants and Events of Default with respect to this Security] [, in
each case] upon compliance with certain conditions set forth in the Indenture.]

     [If the Security is convertible into Common Stock of the Company, insert --
Subject to the provisions of the Indenture, the Holder of this Security is
entitled, at its option, at any time on or before [insert date] (except that, in
case this Security or any portion hereof shall be called for redemption, such
right shall terminate with respect to this Security or portion hereof, as the
case may be, so called for redemption at the close of business on the date fixed
for redemption as provided in the Indenture unless the Company defaults in
making the payment due upon redemption), to convert the principal amount of this
Security (or any portion hereof which is $1,000 or an integral multiple
thereof), into fully paid and non-assessable shares (calculated as to each
conversion to the nearest 1/100th of a share) of the Common Stock of the
Company, as said shares shall be constituted at the date of conversion, at the
conversion price of $______ principal amount of Securities for each share of
Common Stock, or at the adjusted conversion price in effect at the date of
conversion determined as provided in the Indenture, upon surrender of this
Security, together with the conversion notice hereon duly executed, to the
Company at the designated office or agency of the Company in _____________,
accompanied (if so required by the Company) by instruments of transfer, in form
satisfactory to the Company and to the Trustee, duly executed by the Holder or
by its duly authorized attorney in writing. Such surrender shall, if made during
any period beginning at the close of business on a Regular Record Date and
ending at the opening of business on the Interest Payment Date next following
such Regular Record Date (unless this Security or the portion being converted
shall have been called for redemption on a Redemption Date during such period),
also be accompanied by payment in funds acceptable to the Company of an amount
equal to the interest payable on such Interest Payment Date on the principal
amount of this Security then being converted. Subject to the aforesaid
requirement for payment and, in the case of a 

                                      -15-

 
conversion after the Regular Record Date next preceding any Interest Payment
Date and on or before such Interest Payment Date, to the right of the Holder of
this Security (or any Predecessor Security) of record at such Regular Record
Date to receive an installment of interest (with certain exceptions provided in
the Indenture), no adjustment is to be made on conversion for interest accrued
hereon or for dividends on shares of Common Stock issued on conversion. The
Company is not required to issue fractional shares upon any such conversion, but
shall make adjustment therefor in cash on the basis of the current market value
of such fractional interest as provided in the Indenture. The conversion price
is subject to adjustment as provided in the Indenture. In addition, the
Indenture provides that in case of certain consolidations or mergers to which
the Company is a party or the sale of substantially all of the assets of the
Company, the Indenture shall be amended, without the consent of any Holders of
Securities, so that this Security, if then outstanding, will be convertible
thereafter, during the period this Security shall be convertible as specified
above, only into the kind and amount of securities, cash and other property
receivable upon the consolidation, merger or sale by a holder of the number of
shares of Common Stock into which this Security might have been converted
immediately prior to such consolidation, merger or sale (assuming such holder of
Common Stock failed to exercise any rights of election and received per share
the kind and amount received per share by a plurality of non-electing shares) [,
assuming if such consolidation, merger or sale is prior to ________, 19__, that
this Security were convertible at the time of such consolidation, merger or sale
at the initial conversion price specified above as adjusted from _________, 19__
to such time pursuant to the Indenture]. In the event of conversion of this
Security in part only, a new Security or Securities for the unconverted portion
hereof shall be issued in the name of the Holder hereof upon the cancellation
hereof.]

     [If the Security is convertible into other securities of the Company,
specify the conversion features.]

     [If the Security is not an Original Issue Discount Security, insert -- If
an Event of Default with respect to Securities of this series shall occur and be
continuing, the principal of the Securities of this series may be declared due
and payable in the manner and with the effect provided in the Indenture.]

     [If the Security is an Original Issue Discount Security, insert -- If an
Event of Default with respect to Securities of this series shall occur and be
continuing, an amount of principal of the Securities of this series may be
declared due and payable in the manner and with the effect provided in the
Indenture. Such amount shall be equal to -- insert formula for determining the
amount. Upon payment (i) of the amount of principal so declared due and payable
and (ii) of interest on any overdue principal, premium and interest (in each
case to the extent that the payment of such interest shall be legally
enforceable), all of the Company's obligations in respect of the payment of the
principal of and premium and interest, if any, on the Securities of this series
shall terminate.]

     The Indenture permits, with certain exceptions as therein provided, the
amendment thereof and the modification of the rights and obligations of the
Company and the rights of the Holders of the Securities of each series to be
affected under the Indenture at any time by the Company and the Trustee with the
consent of the Holders of more than 50% in principal amount of the Securities at
the time Outstanding of each series to be affected. The Indenture also contains
provisions permitting the Holders of specified percentages in principal amount
of the Securities of each series at the time Outstanding, on behalf of the
Holders of all Securities of such series, to waive compliance by the Company
with certain provisions of the Indenture and certain past defaults under the
Indenture and their consequences. Any such consent or waiver by the Holder of
this Security shall be conclusive and binding upon such Holder 

                                      -16-

 
and upon all future Holders of this Security and of any Security issued upon the
registration of transfer hereof or in exchange herefor or in lieu hereof,
whether or not notation of such consent or waiver is made upon this Security.

     As provided in and subject to the provisions of the Indenture, the Holder
of this Security shall not have the right to institute any proceeding with
respect to the Indenture or for the appointment of a receiver or trustee or for
any other remedy thereunder, unless such Holder shall have previously given the
Trustee written notice of a continuing Event of Default with respect to the
Securities of this series, the Holders of not less than 25% in principal amount
of the Securities of this series at the time Outstanding shall have made written
request to the Trustee to institute proceedings in respect of such Event of
Default as Trustee and offered the Trustee reasonable indemnity, and the Trustee
shall not have received from the Holders of a majority in principal amount of
Securities of this series at the time Outstanding a direction inconsistent with
such request, and shall have failed to institute any such proceeding, for 60
days after receipt of such notice, request and offer of indemnity. The foregoing
shall not apply to any suit instituted by the Holder of this Security for the
enforcement of any payment of principal hereof or any premium or interest hereon
on or after the respective due dates expressed herein.

     No reference herein to the Indenture and no provision of this Security or
of the Indenture shall alter or impair the obligation of the Company, which is
absolute and unconditional, to pay the principal of and any premium and interest
on this Security at the times, place and rate, and in the coin or currency,
herein prescribed.

     As provided in the Indenture and subject to certain limitations therein set
forth, the transfer of this Security is registrable in the Security Register,
upon surrender of this Security for registration of transfer at the office or
agency of the Company in any place where the principal of and any premium and
interest on this Security are payable, duly endorsed by, or accompanied by a
written instrument of transfer in form satisfactory to the Company and the
Security Registrar duly executed by, the Holder hereof or its attorney duly
authorized in writing, and thereupon one or more new Securities of this series
and of like tenor, of authorized denominations and for the same aggregate
principal amount, will be issued to the designated transferee or transferees.

     The Securities of this series are issuable only in registered form without
coupons in denominations of $______ and any integral multiple thereof. As
provided in the Indenture and subject to certain limitations therein set forth,
Securities of this series are exchangeable for a like aggregate principal amount
of Securities of this series and of like tenor of a different authorized
denomination, as requested by the Holder surrendering the same.

     No service charge shall be made for any such registration of transfer or
exchange, but the Company may require payment of a sum sufficient to cover any
tax or other governmental charge payable in connection therewith.

     Prior to due presentment of this 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 this Security is registered as the owner hereof for all
purposes, whether or not this Security be overdue, and neither the Company, the
Trustee nor any such agent shall be affected by notice to the contrary.

                                      -17-

 
     All terms used in this Security which are defined in the Indenture shall
have the meanings assigned to them in the Indenture.

Section 204.  Form of Legend for Global Securities.

     Unless otherwise specified as contemplated by Section 301 for the
Securities evidenced thereby, every Global Security authenticated and delivered
hereunder shall bear a legend in substantially the following form:

     This Security is a Global Security within the meaning of the Indenture
hereinafter referred to and is registered in the name of a Depositary or a
nominee thereof. This Security may not be exchanged in whole or in part for a
Security registered, and no transfer of this Security in whole or in part may be
registered, in the name of any Person other than such Depositary or a nominee
thereof, except in the limited circumstances described in the Indenture.

Section 205.  Form of Trustee's Certificate of Authentication.

     The Trustee's certificates of authentication shall be in substantially the
following form:

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

                     __________________________________________________________,
                                                                      As Trustee

                     By ________________________________________________________
                                                              Authorized Officer
Section 206.  Form of Conversion Notice.

     To Armstrong World Industries, Inc.:

     The undersigned owner of this Security hereby irrevocably exercises the
option to convert this Security, or portion hereof (which is $1,000 or an
integral multiple thereof) below designated, into shares of Common Stock of the
Company in accordance with the terms of the Indenture referred to in this
Security, and directs that the shares issuable and deliverable upon the
conversion, together with any check in payment for fractional shares and any
Securities representing any unconverted principal amount hereof, be issued and
delivered to the registered holder hereof unless a different name has been
indicated below. If this Notice is being delivered on a date after the close of
business on a Regular Record Date and prior to the opening of business on the
related Interest Payment Date (unless this Security or the portion thereof being
converted has been called for redemption on a Redemption Date within such
period), this Notice is accompanied by payment, in funds acceptable to the
Company, of an amount equal to the interest payable on such Interest Payment
Date of the principal of this Security to be converted. If shares are to be
issued in the name of a person other than the undersigned, the undersigned will
pay all transfer taxes payable with respect hereto. Any amount required to be
paid by the undersigned on account of interest accompanies this Security.

                                      -18-

 
Principal Amount to be Converted
(in an integral multiple of
$1,000, if less than all):
$_________________

Dated ________________________

 

                    ________________________________________________________

                    Signature(s) must be guaranteed by a commercial bank or
                    trust company or a member firm of a national stock exchange
                    if shares of Common Stock are to be delivered, or Securities
                    to be issued, other than to and in the name of the
                    registered owner.

                    ________________________________________________________
                                          Signature Guaranty


     Fill in for registration of shares of Common Stock and Security if to be
issued otherwise than to the registered holder.

_____________________________      Social Security or Other Taxpayer
(Name)                             Identification Number _______________________

_____________________________
(Address)

_____________________________
Please print Name and Address
(including zip code number)

[The above conversion notice is to be modified, as appropriate, for conversion
into other securities or property of the Company.]

                                 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.

                                      -19-

 
     The Securities may be issued in one or more series. There shall be
established in or pursuant to a Board Resolution 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,

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

          (2)  any limit upon the aggregate principal amount of the Securities
     of the series which 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 or 1107 and except for any
     Securities which, pursuant to Section 303, are deemed never to have been
     authenticated and delivered hereunder);

          (3)  the Person to whom any interest on a 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;

          (4)  the date or dates on which the principal of any Securities of the
     series is payable;

          (5)  the rate or rates at which any Securities of the series shall
     bear interest, if any, the date or dates from which any such interest shall
     accrue, the Interest Payment Dates on which any such interest shall be
     payable and the Regular Record Date for any such interest payable on any
     Interest Payment Date;

          (6)  the place or places where the principal of and any premium and
     interest on any Securities of the series shall be payable;

          (7)  the period or periods within which, the price or prices at which
     and the terms and conditions upon which any Securities of the series may be
     redeemed, in whole or in part, at the option of the Company and, if other
     than by a Board Resolution, the manner in which any election by the Company
     to redeem the Securities shall be evidenced;

          (8)  the obligation, if any, of the Company to redeem or purchase any
     Securities of the series pursuant to any sinking fund or analogous
     provisions or at the option of the Holder thereof and the period or periods
     within which, the price or prices at which and the terms and conditions
     upon which any Securities of the series shall be redeemed or purchased, in
     whole or in part, pursuant to such obligation;

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

          (10)  if the amount of principal of or any premium or interest on any
     Securities of the series may be determined with reference to an index or
     pursuant to a formula, the manner in which such amounts shall be
     determined;

                                      -20-

 
          (11) if other than the currency of the United States of America, the
     currency, currencies or currency units in which the principal of or any
     premium or interest on any Securities of the series shall be payable and
     the manner of determining the equivalent thereof in the currency of the
     United States of America for any purpose, including for purposes of the
     definition of "Outstanding" in Section 101;

          (12) if the principal of or any premium or interest on any Securities
     of the series is to be payable, at the election of the Company or the
     Holder thereof, in one or more currencies or currency units other than that
     or those in which such Securities are stated to be payable, the currency,
     currencies or currency units in which the principal of or any premium or
     interest on such Securities as to which such election is made shall be
     payable, the periods within which and the terms and conditions upon which
     such election is to be made and the amount so payable (or the manner in
     which such amount shall be determined);

          (13) if other than the entire principal amount thereof, the portion of
     the principal amount of any Securities of the series which shall be payable
     upon declaration of acceleration of the Maturity thereof pursuant to
     Section 502;

          (14) if the principal amount payable at the Stated Maturity of any
     Securities of the series will not be determinable as of any one or more
     dates prior to the Stated Maturity, the amount which shall be deemed to be
     the principal amount of such Securities as of any such date for any purpose
     thereunder or hereunder, including the principal amount thereof which shall
     be due and payable upon any Maturity other than the Stated Maturity or
     which shall be deemed to be Outstanding as of any date prior to the Stated
     Maturity (or, in any such case, the manner in which such amount deemed to
     be the principal amount shall be determined);

          (15) if applicable, that the Securities of the series, in whole or any
     specified part, shall be defeasible pursuant to Section 1302 or Section
     1303 or both such Sections and, if other than by a Board Resolution, the
     manner in which any election by the Company to defease such Securities
     shall be evidenced;

          (16) the terms of any right to convert Securities of the series into
     shares of Common Stock of the Company or other securities or property;

          (17) if applicable, that any Securities of the series shall be
     issuable in whole or in part in the form of one or more Global Securities
     and, in such case, the respective Depositaries for such Global Securities,
     the form of any legend or legends which shall be borne by any such Global
     Security in addition to or in lieu of that set forth in Section 204 and any
     circumstances in addition to or in lieu of those set forth in Clause (2) of
     the last paragraph of Section 305 in which any such Global Security may be
     exchanged in whole or in part for Securities registered, and any transfer
     of such Global Security in whole or in part may be registered, in the name
     or names of Persons other than the Depositary for such Global Security or a
     nominee thereof;

          (18) any addition to or change in the Events of Default which applies
     to any Securities of the series and any change in the right of the Trustee
     or the requisite Holders of 

                                      -21-

 
     such Securities to declare the principal amount thereof due and payable
     pursuant to Section 502;

          (19) any addition to or change in the covenants set forth in Article
     Ten which applies to Securities of the series; and

          (20) any other terms of the series (which terms shall not be
     inconsistent with the provisions of this Indenture, except as permitted by
     Section 901(5)).

     All Securities of any one series shall be substantially identical except as
to denomination and except as may otherwise be provided in or pursuant to the
Board Resolution referred to above and (subject to Section 303) set forth, or
determined in the manner provided, in the Officers' Certificate referred to
above or in any such indenture supplemental hereto.

     If any of the terms of the series are established by action taken pursuant
to a Board Resolution, a copy of an appropriate record of such action 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 series.

     The Securities shall be subordinated in right of payment to Senior Debt as
provided in Article Fifteen.

Section 302.  Denominations.

     The Securities of each series shall be issuable only in registered form
without coupons and only in such denominations as shall be specified as
contemplated by Section 301. In the absence of any such specified denomination
with respect to the Securities of any series, the Securities of such series
shall be issuable in denominations of $1,000 and any integral multiple thereof.

Section 303.  Execution, Authentication, Delivery and Dating.

     The Securities shall be executed on behalf of the Company by its Chairman
of the Board, its Vice Chairman of the Board, its President or one of its Vice
Presidents, under its corporate seal reproduced thereon attested by its
Secretary or one of its Assistant Secretaries. The signature of any of these
officers on the Securities may be manual or facsimile.

     Securities 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.

     At any time and from time to time after the execution and delivery of this
Indenture, the Company may deliver Securities of any series 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. If the
form or terms of the Securities of the series have been established by or
pursuant to one or more Board Resolutions as permitted by Sections 201 and 301,
in authenticating such Securities, and 

                                      -22-

 
accepting the additional responsibilities under this Indenture in relation to
such Securities, the Trustee shall be entitled to receive, and (subject to
Section 601) shall be fully protected in relying upon, an Opinion of Counsel
stating,

          (1) if the form of such Securities has been established by or pursuant
     to Board Resolution as permitted by Section 201, that such form has been
     established in conformity with the provisions of this Indenture;

          (2) if the terms of such Securities have been established by or
     pursuant to Board Resolution as permitted by Section 301, that such terms
     have been established in conformity with the provisions of this Indenture;
     and

          (3) that such Securities, when authenticated and delivered by the
     Trustee and issued by the Company in the manner and subject to any
     conditions specified in such Opinion of Counsel, will constitute valid and
     legally binding obligations of the Company enforceable in accordance with
     their terms, subject to bankruptcy, insolvency, fraudulent transfer,
     reorganization, moratorium and similar laws of general applicability
     relating to or affecting creditors' rights and to general equity
     principles.

     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 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 Securities of a series are not to be originally issued at one
time, it shall not be necessary to deliver the Officers' Certificate otherwise
required pursuant to Section 301 or the Company Order and Opinion of Counsel
otherwise required pursuant to such preceding paragraph at or prior to the
authentication of each Security of such series if such documents are delivered
at or prior to the authentication upon original issuance of the first Security
of such series to be issued.

     Each Security shall be dated the date of its authentication.

     No Security shall be entitled to any benefit under this Indenture or be
valid or obligatory for any purpose unless there appears on such Security a
certificate of authentication substantially in the form provided for herein
executed by the Trustee by manual signature, and such certificate upon any
Security shall be conclusive evidence, and the only evidence, that such Security
has been duly authenticated and delivered hereunder. 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, 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.

     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, 

                                      -23-

 
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 and with such appropriate insertions, omissions,
substitutions and other variations as the officers executing such Securities may
determine, as evidenced by their execution of such Securities.

     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 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, the Company shall execute and the Trustee
shall authenticate and deliver in exchange therefor one or more definitive
Securities of the same series, of any authorized denominations and of like tenor
and aggregate principal amount. 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 and tenor.

Section 305.  Registration; Registration of Transfer and Exchange.

     The Company shall cause to be kept at the Corporate Trust Office of the
Trustee a register (the register maintained in such office and in any other
office or agency of the Company in a Place of Payment being herein sometimes
collectively referred to as the "Security Register") in which, subject to such
reasonable regulations as it may prescribe, the Company shall provide for the
registration of Securities and of transfers of Securities. The Trustee is hereby
appointed "Security Registrar" for the purpose of registering Securities and
transfers of Securities as herein provided.

     Upon surrender for registration of transfer of any Security of a series at
the 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 Securities of
the same series, of any authorized denominations and of like tenor and aggregate
principal amount.

     At the option of the Holder, Securities of any series may be exchanged for
other Securities of the same series, of any authorized denominations and of like
tenor and aggregate principal amount, upon surrender of the Securities to be
exchanged at such office or agency. Whenever any 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.

     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 Security presented or surrendered for registration of transfer or for
exchange shall (if so required by the Company or the Trustee) 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
its attorney duly authorized in writing.

                                      -24-

 
     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 or 1107 not involving any transfer.

     If the Securities of any series (or of any series and specified tenor) are
to be redeemed in part, the Company shall not be required (A) to issue, register
the transfer of or exchange any Securities of that series (or of that series and
specified tenor, as the case may be) during a period beginning at the opening of
business 15 days before the day of the mailing of a notice of redemption of any
such Securities selected for redemption under Section 1103 and ending at the
close of business on the day of such mailing, or (B) to register the transfer of
or exchange any Security so selected for redemption in whole or in part, except
the unredeemed portion of any Security being redeemed in part.

     The provisions of Clauses (1), (2), (3) and (4) below shall apply only to
Global Securities:

          (1) Each Global Security authenticated under this Indenture shall be
     registered in the name of the Depositary designated for such Global
     Security or a nominee thereof and delivered to such Depositary or a nominee
     thereof or custodian therefor, and each such Global Security shall
     constitute a single Security for all purposes of this Indenture.

          (2) Notwithstanding any other provision in this Indenture, no Global
     Security may be exchanged in whole or in part for Securities registered,
     and no transfer of a Global Security in whole or in part may be registered,
     in the name of any Person other than the Depositary for such Global
     Security or a nominee thereof unless (A) such Depositary (i) has notified
     the Company that it is unwilling or unable to continue as Depositary for
     such Global Security or (ii) has ceased to be a clearing agency registered
     under the Exchange Act, (B) there shall have occurred and be continuing an
     Event of Default with respect to such Global Security or (C) there shall
     exist such circumstances, if any, in addition to or in lieu of the
     foregoing as have been specified for this purpose as contemplated by
     Section 301.

          (3) Subject to Clause (2) above, any exchange of a Global Security for
     other Securities may be made in whole or in part, and all Securities issued
     in exchange for a Global Security or any portion thereof shall be
     registered in such names as the Depositary for such Global Security shall
     direct.

          (4) Every Security authenticated and delivered upon registration of
     transfer of, or in exchange for or in lieu of, a Global Security or any
     portion thereof, whether pursuant to this Section, Section 304, 306, 906 or
     1107 or otherwise, shall be authenticated and delivered in the form of, and
     shall be, a Global Security, unless such Security is registered in the name
     of a Person other than the Depositary for such Global Security or a nominee
     thereof.

Section 306.  Mutilated, Destroyed, Lost and Stolen Securities.

     If any mutilated Security is surrendered to the Trustee, the Company shall
execute and the Trustee shall authenticate and deliver in exchange therefor a
new Security of the same series and of like tenor and principal amount and
bearing a number not contemporaneously outstanding.

                                      -25-

 
     If there shall be delivered to the Company and the Trustee (i) evidence to
their satisfaction of the destruction, loss or theft of any Security 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 notice to the
Company or the Trustee that such Security has been acquired by a bona fide
purchaser, the Company shall execute and the Trustee shall authenticate and
deliver, in lieu of any such destroyed, lost or stolen Security, a new Security
of the same series and of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

     In case any such mutilated, destroyed, lost or stolen Security has become
or is about to become due and payable, the Company in its discretion may,
instead of issuing a new Security, pay such Security.

     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 issued pursuant to this Section in lieu of
any destroyed, lost or stolen Security shall constitute an original additional
contractual obligation of the Company, whether or not the destroyed, lost or
stolen Security 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 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.

Section 307.  Payment of Interest; Interest Rights Preserved.

     Except as otherwise provided as contemplated by Section 301 with respect to
any series of Securities, interest on any Security which 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.

     Any interest on any Security of any series which 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 Holder
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 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 Security of such series and the date of the proposed payment, and
     at the same time the 

                                      -26-

 
     Company shall deposit with the Trustee an amount of money 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
     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
     be not 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 given to each
     Holder of Securities of such series in the manner set forth in Section 106,
     not less than 10 days prior to such Special Record Date. Notice of the
     proposed payment of such Defaulted Interest and the Special Record Date
     therefor having been so mailed, such Defaulted Interest shall be paid to
     the Persons in whose names the 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).

          (2) The Company may make payment of any Defaulted Interest on the
     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, 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.

     Subject to the provisions of Section 1402, in the case of any Security (or
any part thereof) which is converted after any Regular Record Date and on or
prior to the next succeeding Interest Payment Date (other than any Security the
principal of (or premium, if any, on) which shall become due and payable,
whether at Stated Maturity or by declaration of acceleration prior to such
Interest Payment Date), interest whose Stated Maturity is on such Interest
Payment Date shall be payable on such Interest Payment Date notwithstanding such
conversion and such interest (whether or not punctually paid or duly provided
for) shall be paid to the Person in whose name that Security (or any one or more
Predecessor Securities) is registered at the close of business on such Regular
Record Date. Except as otherwise expressly provided in the immediately preceding
sentence or in Section 1402, in the case of any Security (or any part thereof)
which is converted, interest whose Stated Maturity is after the date of
conversion of such Security (or such part thereof) shall not be payable.

Section 308.  Persons Deemed Owners.

     Prior to due presentment of a 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 Security is registered as the owner of such Security
for the purpose of receiving payment of principal of and any premium and
(subject to Section 307) any interest on such Security and for all other
purposes 

                                      -27-

 
whatsoever, whether or not such Security be overdue, and neither the Company,
the Trustee nor any agent of the Company or the Trustee shall be affected by
notice to the contrary.

Section 309.  Cancellation.

     All Securities surrendered for payment, redemption, 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 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. 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. All cancelled
Securities held by the Trustee shall be disposed of as directed by a Company
Order.

Section 310.  Computation of Interest.

     Except as otherwise specified as contemplated by Section 301 for Securities
of any series, interest on the Securities of each series shall be computed on
the basis of a 360-day year 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
(except as to any surviving rights of registration of transfer or exchange of
Securities herein expressly provided for), and the Trustee, at the expense of
the Company, shall execute proper instruments acknowledging satisfaction and
discharge of this Indenture, when

          (1)  either

               (A) all Securities theretofore authenticated and delivered (other
          than (i) Securities which have been destroyed, lost or stolen and
          which have been replaced or paid as provided in Section 306 and (ii)
          Securities 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 such Securities not theretofore delivered to the Trustee
          for cancellation

                   (i)    have become due and payable, or

                                      -28-

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

                   (iii)  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
          deposited or caused to be deposited with the Trustee as trust funds in
          trust for the purpose money in an amount sufficient to pay and
          discharge the entire indebtedness on such Securities not theretofore
          delivered to the Trustee for cancellation, for principal and any
          premium and interest 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 have been complied with.

     Notwithstanding the satisfaction and discharge of this Indenture, the
obligations of the Company to the Trustee under Section 607, the obligations of
the Trustee to any Authenticating Agent under Section 614 and, if money shall
have been deposited with 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.

Section 402.  Application of Trust Money.

     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 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 any premium and
interest for whose payment such money has been deposited with the Trustee.

                                  ARTICLE FIVE

                                    Remedies

Section 501.  Events of Default.

     "Event of Default", wherever used herein with respect to Securities of any
series, means any one of the following events (whatever the reason for such
Event of Default and whether it shall be occasioned by the provisions of Article
Fifteen or 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):

                                      -29-

 
          (1) default in the payment of any interest upon any Security of that
     series when it 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 any premium on any
     Security of that series at its Maturity; or

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

          (4) default in the performance, or breach, of any covenant or warranty
     of the Company in this Indenture (other than a covenant or warranty a
     default in whose performance or whose breach is elsewhere in this Section
     specifically dealt with or which has expressly been included in this
     Indenture solely for the benefit of 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
     25% 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) the entry by a court having jurisdiction in the premises of (A) a
     decree or order for relief in respect of the Company in an involuntary case
     or proceeding under any applicable Federal or State bankruptcy, insolvency,
     reorganization or other similar law or (B) a decree or order adjudging the
     Company a bankrupt or insolvent, or approving as properly filed a petition
     seeking reorganization, arrangement, adjustment or composition of or in
     respect of the Company under any applicable Federal or State law, or
     appointing a custodian, receiver, liquidator, assignee, trustee,
     sequestrator or other similar official of the Company or of any substantial
     part of its property, or ordering the winding up or liquidation of its
     affairs, and the continuance of any such decree or order for relief or any
     such other decree or order unstayed and in effect for a period of 90
     consecutive days; or

          (6) the commencement by the Company of a voluntary case or proceeding
     under any applicable Federal or State bankruptcy, insolvency,
     reorganization or other similar law or of any other case or proceeding to
     be adjudicated a bankrupt or insolvent, or the consent by it to the entry
     of a decree or order for relief in respect of the Company in an involuntary
     case or proceeding under any applicable Federal or State bankruptcy,
     insolvency, reorganization or other similar law or to the commencement of
     any bankruptcy or insolvency case or proceeding against it, or the filing
     by it of a petition or answer or consent seeking reorganization or relief
     under any applicable Federal or State law, or the consent by it to the
     filing of such petition or to the appointment of or taking possession by a
     custodian, receiver, liquidator, assignee, trustee, sequestrator or other
     similar official of the Company or of any substantial part of its property,
     or the making by it of an assignment for the benefit of creditors, or the
     admission by it in writing of its inability to pay its debts generally as
     they become due, or the taking of corporate action by the Company in
     furtherance of any such action; or

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

                                      -30-

 
Section 502.  Acceleration of Maturity; Rescission and Annulment.

     If an Event of Default (other than an Event of Default specified in Section
501(5) or 501(6)) with respect to Securities of any series at the time
Outstanding occurs and is continuing, then in every such case the Trustee or the
Holders of not less than 25% in principal amount of the Outstanding Securities
of that series may declare the principal amount of all the Securities of that
series (or, if any Securities of that series are Original Issue Discount
Securities, such portion of the principal amount of such Securities as may be
specified by the terms thereof) to be due and payable immediately, by a notice
in writing to the Company (and to the Trustee if given by Holders), and upon any
such declaration such principal amount (or specified amount) shall become
immediately due and payable. If an Event of Default specified in Section 501(5)
or 501 (6) with respect to Securities of any series at the time Outstanding
occurs, the principal amount of all the Securities of that series (or, if any
Securities of that series are Original Issue Discount Securities, such portion
of the principal amount of such Securities as may be specified by the terms
thereof) shall automatically, and without any declaration or other action on the
part of the Trustee or any Holder, 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

          (1)  the Company has paid or deposited with the Trustee a sum
     sufficient to pay

               (A) all overdue interest on all Securities of that series,

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

               (C) to the extent that payment of such interest is lawful,
          interest upon overdue interest at the rate or rates prescribed
          therefor 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 non-payment of the principal of 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.

                                      -31-

 
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 interest on any Security
     when such interest 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 at the Maturity thereof,

the Company will, upon demand of the Trustee, pay to it, for the benefit of the
Holders of such Securities, the whole amount then due and payable on such
Securities for principal and any premium and interest and, to the extent that
payment of such interest shall be legally enforceable, interest on any overdue
principal and premium and on any overdue interest, at the rate or rates
prescribed therefor 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 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 by such
appropriate judicial proceedings as the Trustee shall deem most effectual to
protect and 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 any judicial proceeding relative to the Company (or any other
obligor upon the Securities), its property or its creditors, the Trustee shall
be entitled and empowered, by intervention in such proceeding or otherwise, to
take any and all actions authorized under the Trust Indenture Act in order to
have claims of the Holders and the Trustee allowed in any such proceeding. In
particular, the Trustee shall be authorized 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 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 it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, and any other
amounts due the Trustee under Section 607.

     No provision of this Indenture shall be deemed to authorize the Trustee to
authorize or consent to or accept or adopt on behalf of any Holder any plan of
reorganization, arrangement, adjustment or composition affecting the Securities
or the rights of any Holder thereof or to authorize the Trustee to vote in
respect of the claim of any Holder in any such proceeding; provided, however,
that the Trustee may, on behalf of the Holders, vote for the election of a
trustee in bankruptcy or similar official and be a member of a creditors' or
other similar committee.

                                      -32-

 
Section 505.  Trustee May Enforce Claims Without Possession of Securities.

     All rights of action and claims under this Indenture or the Securities may
be prosecuted and enforced by the Trustee without the possession of any of the
Securities 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 the Securities 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 any premium
or interest, upon presentation of the Securities 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 the Trustee under Section 607; and

     Second: Subject to Article Fifteen, to the payment of the amounts then due
and unpaid for principal of and any premium and interest on the Securities in
respect of which or for the benefit of which such money has been collected,
ratably, without preference or priority of any kind, according to the amounts
due and payable on such Securities for principal and any premium and interest,
respectively.

Section 507.  Limitation on Suits.

     No Holder of any Security of any series 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 25% 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;

                                      -33-

 
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 of such
Holders.

Section 508.  Unconditional Right of Holders to Receive Principal, Premium and
              Interest and to Convert.
  
     Notwithstanding any other provision in this Indenture, the Holder of any
Security shall have the right, which is absolute and unconditional, to receive
payment of the principal of and any premium and (subject to Section 307)
interest on such Security on the respective Stated Maturities expressed in such
Security (or, in the case of redemption, on the Redemption Date), to convert
such Securities in accordance with Article Fourteen 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 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, subject to any determination in
such proceeding, the Company, the Trustee and the Holders shall 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 in the last paragraph of Section
306, no right or remedy herein conferred upon or reserved to the Trustee or to
the Holders is intended to be exclusive of any other right or remedy, and every
right and remedy shall, to the extent permitted by law, 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 Securities 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, as the case may
be.

                                      -34-

 
Section 512.  Control by Holders.

     The Holders of 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, and

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

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 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 any premium or interest on
     any Security of such series, 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 impair any right consequent thereon.

Section 514.  Undertaking for Costs.

     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, suffered or
omitted by it as Trustee, a court may require any party litigant in such suit to
file an undertaking to pay the costs of such suit, and may assess costs against
any such party litigant, in the manner and to the extent provided in the Trust
Indenture Act; provided that neither this Section nor the Trust Indenture Act
shall be deemed to authorize any court to require such an undertaking or to make
such an assessment in any suit instituted by the Company, by the Trustee or in
any suit for the enforcement of the right to convert any Security in accordance
with Article Fourteen.

Section 515.  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

                                      -35-

 
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.

                                  ARTICLE SIX

                                  The Trustee

Section 601.  Certain Duties and Responsibilities.

     The duties and responsibilities of the Trustee shall be as provided by the
Trust Indenture Act. Notwithstanding the foregoing, no provision of this
Indenture shall require the Trustee 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, if it shall have reasonable
grounds for believing that repayment of such funds or adequate indemnity against
such risk or liability is not reasonably assured to it. Whether or not therein
expressly so provided, every provision of this Indenture relating to the conduct
or affecting the liability of or affording protection to the Trustee shall be
subject to the provisions of this Section.

Section 602.  Notice of Defaults.

     If a default occurs hereunder with respect to Securities of any series, the
Trustee shall give the Holders of Securities of such series notice of such
default as and to the extent provided by the Trust Indenture Act; provided,
however, that in the case of any default of the character specified in Section
501(4) with respect to Securities of such series, no such notice to Holders
shall be given until at least 30 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 Securities of such series.

Section 603.  Certain Rights of Trustee.

     Subject to the provisions of Section 601:

          (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, other evidence of indebtedness 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, and any
     resolution of the Board of Directors shall 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 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;

                                      -36-

 
          (4) the Trustee may consult with counsel and the written 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 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;

          (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, other evidence of indebtedness 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; and

          (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.

Section 604.  Not Responsible for Recitals or Issuance of Securities.

     The recitals contained herein and in the Securities, except the Trustee's
certificates of authentication, 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. Neither the Trustee nor
any Authenticating Agent shall be accountable for the use or application by the
Company of Securities or the proceeds thereof.

Section 605.  May Hold Securities.

     The Trustee, any Authenticating Agent, any Paying Agent, any Security
Registrar or any other agent of the Company, in its individual or any other
capacity, may become the owner or pledgee of Securities and, subject to Sections
608 and 613, may otherwise deal with the Company with the same rights it would
have if it were not Trustee, Authenticating Agent, Paying Agent, Security
Registrar or such other agent.

Section 606.  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.

                                      -37-

 
Section 607.  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 the
     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 the Trustee for, and to hold it harmless against, any
     loss, liability or expense incurred without negligence or bad faith on its
     part, arising out of or in connection with the acceptance or administration
     of the trust or trusts hereunder, including the costs 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.

     The provisions of this Section 607 shall survive the termination of this 
Indenture and the resignation or removal of the Trustee.

Section 608.  Conflicting Interests.

     If the Trustee has or shall acquire a conflicting interest within the
meaning of the Trust Indenture Act, the Trustee shall either eliminate such
interest or resign, to the extent and in the manner provided by, and subject to
the provisions of, the Trust Indenture Act and this Indenture. To the extent
permitted by such Act, the Trustee shall not be deemed to have a conflicting
interest by virtue of being a trustee under this Indenture with respect to
Securities of more than one series or the trustee under the Indenture, dated as
of the date hereof, between the Company and the Trustee, relating to the Senior
Debt Securities, or the trustee under the Indenture, dated as of March 15, 1988,
between the Company and Morgan Guaranty Trust Company of New York, as trustee,
as supplemented by the Supplemental Indenture, dated as of October 19, 1990,
between the Company and The First National Bank of Chicago, as successor
trustee.

Section 609.  Corporate Trustee Required; Eligibility.

     There shall at all times be one (and only one) Trustee hereunder with
respect to the Securities of each series, which may be Trustee hereunder for
Securities of one or more other series. Each Trustee shall be a Person that is
eligible pursuant to the Trust Indenture Act to act as such and has a combined
capital and surplus of at least $100,000,000. If any such Person publishes
reports of condition at least annually, pursuant to law or to the requirements
of its supervising or examining authority, then for the purposes of this Section
and to the extent permitted by the Trust Indenture Act, the combined capital and
surplus of such Person 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 with respect to the Securities of any series 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.

                                      -38-

 
Section 610.  Resignation and Removal; Appointment of Successor.

     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 611.

     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 the instrument
of acceptance by a successor Trustee required by Section 611 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 with respect to the
Securities of such series.

     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.

     If at any time:

          (1) the Trustee shall fail to comply with Section 608 after written
     request therefor by the Company or by any Holder 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 609 and shall
     fail to resign after written request therefor by the Company or by any such
     Holder, 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,

then, in any such case, (A) the Company by a Board Resolution may remove the
Trustee with respect to all Securities, or (B) subject to Section 514, any
Holder 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.

     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 cause, with respect to
the Securities of one or more series, the Company, by 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) and shall comply with the applicable
requirements of Section 611. 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 in accordance
with the applicable

                                      -39-

 
requirements of Section 611, 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 and
accepted appointment in the manner required by Section 611, any Holder 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 the Securities of such series.

     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 to all Holders of
Securities of such series in the manner provided 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 611.  Acceptance of Appointment by Successor.

     In case of the appointment hereunder of a successor Trustee with respect to
all Securities, every such successor Trustee so appointed 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, on the 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.

     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 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 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

                                      -40-

 
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.

     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 the
first or second preceding paragraph, as the case may be.

     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 612.  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 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 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 so authenticated with the same effect
as if such successor Trustee had itself authenticated such Securities.

Section 613.  Preferential Collection of Claims Against Company.

     If and when the Trustee shall be or become a creditor of the Company (or
any other obligor upon the Securities), the Trustee shall be subject to the
provisions of the Trust Indenture Act regarding the collection of claims against
the Company (or any such other obligor).

Section 614.  Appointment of Authenticating Agent.

     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 original issue
and upon exchange, registration of transfer or partial redemption thereof or
pursuant to Section 306, 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. 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 shall at all times be a corporation organized and
doing business under the laws of the United States of America, any State thereof
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 authority. If such
Authenticating Agent publishes reports of condition at least annually, pursuant
to law or to the requirements of said 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. If at any time an
Authenticating Agent shall cease to be eligible in accordance with the
provisions of this Section,

                                      -41-

 
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 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 any further
act on the part of the Trustee or the Authenticating Agent.

     An Authenticating Agent may resign at any time by giving written notice
thereof to the Trustee and to the Company. The Trustee may at any time terminate
the agency of an Authenticating Agent by giving written notice thereof 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 may appoint a successor Authenticating
Agent which shall be acceptable to the Company and shall give notice of such
appointment in the manner provided in Section 106 to all Holders of Securities
of the series with respect to which such Authenticating Agent will serve. 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.
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 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 the Trustee's certificate of authentication, an alternative
certificate of authentication 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

                                      -42-

 
                                 ARTICLE SEVEN

               Holders' Lists and Reports by Trustee and Company

Section 701.  Company to Furnish Trustee Names and Addresses of Holders.

     The Company will furnish or cause to be furnished to the Trustee

          (1) semi-annually, not later than January 15 and July 15 in each year,
     a list, in such form as the Trustee may reasonably require, of the names
     and addresses of the Holders of Securities of each series as of the
     preceding January 1 or July 1, as the case may be, and

          (2) 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;

excluding from any such list names and addresses received by the Trustee in its
capacity as Security Registrar.

Section 702.  Preservation of Information; Communications to Holders.

     The Trustee shall preserve, in as current a form as is reasonably
practicable, the names and addresses of Holders contained in the most recent
list furnished to the Trustee as provided in Section 701 and the names and
addresses of Holders received by the Trustee in its capacity as Security
Registrar. The Trustee may destroy any list furnished to it as provided in
Section 701 upon receipt of a new list so furnished.

     The rights of Holders to communicate with other Holders with respect to
their rights under this Indenture or under the Securities, and the corresponding
rights and privileges of the Trustee, shall be as provided by the Trust
Indenture Act.

     Every Holder of Securities, by receiving and holding the same, agrees with
the Company and the Trustee that neither the Company nor the Trustee nor any
agent of either of them shall be held accountable by reason of any disclosure of
information as to names and addresses of Holders made pursuant to the Trust
Indenture Act.

Section 703.  Reports by Trustee.

     The Trustee shall transmit to Holders such reports concerning the Trustee
and its actions under this Indenture as may be required pursuant to the Trust
Indenture Act at the times and in the manner provided pursuant thereto.

     Reports so required to be transmitted at stated intervals of not more than
12 months shall be transmitted no later than July 1 in each calendar year,
commencing in 1999.

     A copy of each such report shall, at the time of such transmission to
Holders, be filed by the Trustee with each stock exchange upon which any
Securities are listed, with the Commission and with

                                      -43-

 
the Company. The Company will notify the Trustee when any Securities are listed
on any stock exchange.

Section 704.  Reports by Company.

     The Company shall file with the Trustee and the Commission, and transmit to
Holders, such information, documents and other reports, and such summaries
thereof, as may be required pursuant to the Trust Indenture Act at the times and
in the manner provided pursuant to the Trust Indenture Act; provided that any
such information, documents or reports required to be filed with the Commission
pursuant to Section 13 or 15(d) of the Exchange Act shall be filed with the
Trustee within 15 days after the same is so required to be filed with the
Commission.

                                 ARTICLE EIGHT

             Consolidation, Merger, Conveyance, Transfer or Lease

Section 801.  Company May Consolidate, Etc., Only on Certain Terms.

     The Company shall not consolidate with or merge into any other Person or
convey, transfer or lease its properties and assets substantially as an entirety
to any Person, and the Company shall not permit any Person to consolidate with
or merge into the Company or convey, transfer or lease its properties and assets
substantially as an entirety to the Company, unless:

          (1) in case the Company shall consolidate with or merge into another
     Person or convey, transfer or lease its properties and assets substantially
     as an entirety to any Person, the Person formed by such consolidation or
     into which the Company is merged or the Person which acquires by conveyance
     or transfer, or which leases, the properties and assets of the Company
     substantially as an entirety shall be a corporation, partnership or trust,
     shall be organized and validly existing under the laws of the United States
     of America, any State thereof or the District of Columbia and shall
     expressly assume, by an indenture supplemental hereto, executed and
     delivered to the Trustee, in form satisfactory to the Trustee, the due and
     punctual payment of the principal of and any premium and interest on all
     the Securities and the performance or observance of every covenant of this
     Indenture on the part of the Company to be performed or observed and the
     conversion rights shall be provided for in accordance with Article
     Fourteen, if applicable, or as otherwise specified pursuant to Section 301,
     by supplemental indenture satisfactory in form to the Trustee, executed and
     delivered to the Trustee, by the Person (if other than the Company) formed
     by such consolidation or into which the Company shall have been merged or
     by the Person which shall have acquired the Company's assets;

          (2) immediately after giving effect to such transaction and treating
     any indebtedness which becomes an obligation of the Company or any
     Subsidiary as a result of such transaction as having been incurred by the
     Company or such Subsidiary at the time of such transaction, no Event of
     Default, and no event which, after notice or lapse of time or both, would
     become an Event of Default, shall have happened and be continuing;

          (3) if, as a result of any such consolidation or merger or such
     conveyance, transfer or lease, properties or assets of the Company would
     become subject to a Lien which would not

                                      -44-

 
     be permitted by this Indenture, the Company or such successor Person, as
     the case may be, shall take such steps as shall be necessary effectively to
     secure the Securities equally and ratably with (or prior to) all
     indebtedness secured thereby; and

          (4) the Company has delivered to the Trustee an Officers' Certificate
     and an Opinion of Counsel, each stating that such consolidation, merger,
     conveyance, transfer or lease and, if a supplemental indenture is required
     in connection with such transaction, such supplemental indenture comply
     with this Article and that all conditions precedent herein provided for
     relating to such transaction have been complied with.

Section 802.  Successor Substituted.

     Upon any consolidation of the Company with, or merger of the Company into,
any other Person or any conveyance, transfer or lease of the properties and
assets of the Company substantially as an entirety in accordance with Section
801, the successor Person formed by such consolidation or into which the Company
is merged or to which such conveyance, transfer or lease is made shall succeed
to, and be substituted for, and may exercise every right and power of, the
Company under this Indenture with the same effect as if such successor Person
had been named as the Company herein, and thereafter, except in the case of a
lease, the predecessor Person shall be relieved of all obligations and covenants
under this Indenture and the Securities.

                                 ARTICLE NINE

                            Supplemental Indentures

Section 901.  Supplemental Indentures Without Consent of Holders.

     Without the consent of any Holders, the Company, when authorized by 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; 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

          (3) to add any additional Events of Default for the benefit of the
     Holders of all or any series of Securities (and if such additional Events
     of Default are to be for the benefit of less than all series of Securities,
     stating that such additional Events of Default are expressly being included
     solely for the benefit of such series); or

          (4) to add to or change any of the provisions of this Indenture to
     such extent as shall be necessary to permit or facilitate the issuance of
     Securities in bearer form, registrable or

                                      -45-

 
     not registrable as to principal, and with or without interest coupons, or
     to permit or facilitate the issuance of Securities in uncertificated form;
     or

          (5)  to add to, change or eliminate any of the provisions of this
     Indenture in respect of one or more series of Securities, provided that any
     such addition, change or elimination (A) shall neither (i) apply to any
     Security of any series created prior to the execution of such supplemental
     indenture and entitled to the benefit of such provision nor (ii) modify the
     rights of the Holder of any such Security with respect to such provision or
     (B) shall become effective only when there is no such Security Outstanding;
     or

          (6)  to secure the Securities; or

          (7)  to establish the form or terms of Securities of any series as
     permitted by Sections 201 and 301; 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, pursuant to the requirements
     of Section 611; or

          (9)  to make provision with respect to the conversion rights of
     Holders pursuant to the requirements of Article Fourteen, including
     providing for the conversion of the securities into any security (other
     than the Common Stock of the Company) or property of the Company; or

          (10) 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, provided that such action pursuant
     to this Clause (9) shall not adversely affect the interests of the Holders
     of Securities of any series in any material respect.

Section 902.  Supplemental Indentures With Consent of Holders.

     With the consent of the Holders of more than 50% in principal amount of the
Outstanding Securities of each series affected by such supplemental indenture,
by Act of said Holders delivered to the Company and the Trustee, the Company,
when authorized by 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 of such series under this Indenture; provided, 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 any instalment
     of principal of or interest on, any Security, or reduce the principal
     amount thereof or the rate of interest thereon or any premium payable upon
     the redemption thereof, or reduce the amount of the principal of an
     Original Issue Discount Security or any other Security which would be due
     and payable

                                      -46-

 
     upon a declaration of acceleration of the Maturity thereof pursuant to
     Section 502, or change any Place of Payment where, or the coin or currency
     in which, any Security or any premium or 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, on
     or after the Redemption Date), or modify the provisions of this Indenture
     with respect to the subordination of the Securities in a manner adverse to
     the Holders, 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 (of compliance with certain provisions of this Indenture or
     certain defaults hereunder and their consequences) provided for in this
     Indenture, or

          (3) modify any of the provisions of this Section, Section 513 or
     Section 1008, except to increase any such percentage 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; provided, however, that this clause shall not be deemed to require
     the consent of any Holder with respect to changes in the references to "the
     Trustee" and concomitant changes in this Section and Section 1008, or the
     deletion of this proviso, in accordance with the requirements of Sections
     611 and 901(8), or

          (4) if applicable, make any change that adversely affects the right to
     convert any security as provided in Article Fourteen or pursuant to Section
     301 (except as permitted by Section 901(9)) or decrease the conversion rate
     or increase the conversion price of any such security.

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.

     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.

Section 903.  Execution of Supplemental Indentures.

     In executing, or accepting the additional trusts created by, any
supplemental indenture permitted by this Article or the modifications thereby of
the trusts created by this Indenture, the Trustee shall be entitled to receive,
and (subject to Section 601) 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.

                                      -47-

 
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
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.

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.

Section 907.  Subordination Unimpaired.

     No provision in any supplemental indenture which affects the superior
position of the holders of Senior Debt shall be effective against holders of
Senior Debt.

                                  ARTICLE TEN

                                   Covenants

Section 1001. Payment of Principal, Premium and Interest.

     The Company covenants and agrees for the benefit of each series of
Securities that it will duly and punctually pay the principal of and any premium
and interest on the Securities of that series in accordance with the terms of
the Securities and this Indenture.

Section 1002. Maintenance of Office or Agency.

     The Company will 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, where Securities of that series may be surrendered
for registration of transfer or exchange, where Securities of that series may be
surrendered for conversion 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 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

                                      -48-

 
served at the Corporate Trust Office of the Trustee, and the Company hereby
appoints the Trustee as its agent to receive all such presentations, surrenders,
notices and demands.

     The Company may also 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 such purposes and may from time to time rescind such
designations; 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 each Place of Payment 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.

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 Securities, it will, on or before each due date of the
principal of or any premium or interest on any of the Securities of that series,
segregate and hold in trust for the benefit of the Persons entitled thereto a
sum sufficient to pay the principal and any premium and interest 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, it will, prior to each due date of the principal of or any premium
or interest on any Securities of that series, deposit with a Paying Agent a sum
sufficient to pay such amount, such sum to be held as provided by the Trust
Indenture Act, 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 for any series of Securities 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 (1) comply with the provisions of the
Trust Indenture Act applicable to it as a Paying Agent and (2) during the
continuance of any default by the Company (or any other obligor upon the
Securities of that series) in the making of any payment in respect of the
Securities of that series, upon the written request of the Trustee, forthwith
pay to the Trustee all sums held in trust by such Paying Agent for payment in
respect of the Securities of that series.

     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
money.

     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 or any premium or
interest on any Security of any series and remaining unclaimed for two years
after such principal, premium or interest has become due and payable shall be
paid to the Company on 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

                                      -49-

 
creditor, look only to the Company for payment thereof, 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 a
newspaper published in the English language, customarily published on each
Business Day and of general circulation in each Place of Payment, 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.  Statement by Officers as to Default.

     The Company will deliver to the Trustee, within 120 days after the end of
each fiscal year of the Company ending after the date hereof, an Officers'
Certificate, stating whether or not to the best knowledge of the signers thereof
the Company is in default in the performance and observance of any of the terms,
provisions and conditions of this Indenture (without regard to any period of
grace or requirement of notice provided hereunder) and, if the Company shall be
in default, specifying all such defaults and the nature and status thereof of
which they may have knowledge.

Section 1005.  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 (charter and statutory) and franchises; provided, however, that the
Company shall not be required to preserve any such right or franchise if the
Board of Directors shall determine that the preservation thereof is no longer
desirable in the conduct of the business of the Company and that the loss
thereof is not disadvantageous in any material respect to the Holders.

Section 1006.  Maintenance of Properties.

     The Company will cause all properties used or useful in the conduct of its
business or the business of any Subsidiary to be maintained and kept in good
condition, repair and working order and supplied with all necessary equipment
and will cause to be made all necessary repairs, renewals, replacements,
betterments and improvements thereof, all as in the judgment of the Company may
be necessary so that the business carried on in connection therewith may be
properly and advantageously conducted at all times; provided, however, that
nothing in this Section shall prevent the Company from discontinuing the
operation or maintenance of any of such properties if such discontinuance is, in
the judgment of the Company, desirable in the conduct of its business or the
business of any Subsidiary and not disadvantageous in any material respect to
the Holders.

Section 1007.  Payment of Taxes and Other Claims.

     The Company will pay or discharge or cause to be paid or discharged, before
the same shall become delinquent, (1) all taxes, assessments and governmental
charges levied or imposed upon the Company or any Subsidiary or upon the income,
profits or property of the Company or any Subsidiary, and (2) all lawful claims
for labor, materials and supplies which, if unpaid, might by law become a lien
upon the property of the Company or any Subsidiary; provided, however, that the
Company shall not be

                                      -50-

 
required to pay or discharge or cause to be paid or discharged any such tax,
assessment, charge or claim whose amount, applicability or validity is being
contested in good faith by appropriate proceedings.

Section 1008.  Waiver of Certain Covenants.

     Except as otherwise specified as contemplated by Section 301 for Securities
of such series, the Company may, with respect to the Securities of any series,
omit in any particular instance to comply with any term, provision or condition
set forth in any covenant provided pursuant to Section 301(19), 901(2) or 901(7)
for the benefit of the Holders of such series if before the time for such
compliance the Holders of at least 50% in principal amount of the Outstanding
Securities of such series shall, by Act of such Holders, either waive such
compliance in such instance or generally waive compliance with such term,
provision or condition, but no such waiver shall extend to or affect such term,
provision 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.

                                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 such Securities) 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
a Board Resolution or in another manner specified as contemplated by Section 301
for such Securities. In case of any redemption at the election of the Company of
less than all the Securities of any series (including any such redemption
affecting only a single Security), the Company shall, at least 60 days prior to
the Redemption Date fixed by the Company (unless a shorter notice shall be
satisfactory to the Trustee), notify the Trustee of such Redemption Date, of the
principal amount of Securities of such series to be redeemed and, if applicable,
of the tenor of the Securities 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 are to be redeemed (unless
all the Securities of such series and of a specified tenor are to be redeemed or
unless such redemption affects only a single Security), 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
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 a
portion of the principal amount of any Security of such series, 

                                      -51-

 
provided that the unredeemed portion of the principal amount of any Security
shall be in an authorized denomination (which shall not be less than the minimum
authorized denomination) for such Security. If less than all the Securities of
such series and of a specified tenor are to be redeemed (unless such redemption
affects only a single Security), 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 and specified tenor not
previously called for redemption in accordance with the preceding sentence.

     If any Security selected for partial redemption is converted in part before
termination of the conversion right with respect to the portion of the Security
so selected, the converted portion of such Security shall be deemed (so far as
may be) to be the portion selected for redemption. Securities which have been
converted during a selection of Securities to be redeemed shall be treated by
the Trustee as Outstanding for the purpose of such selection.

     The Trustee shall promptly notify the Company in writing of the Securities
selected for redemption as aforesaid and, in case of any Securities selected for
partial redemption as aforesaid, the principal amount thereof to be redeemed.

     The provisions of the two preceding paragraphs shall not apply with respect
to any redemption affecting only a single Security, whether such Security is to
be redeemed in whole or in part. In the case of any such redemption in part, the
unredeemed portion of the principal amount of the Security shall be in an
authorized denomination (which shall not be less than the minimum authorized
denomination) for such Security.

     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 Securities redeemed or to be redeemed only in part, to the portion
of the principal amount of such Securities which has been or is to be redeemed.

Section 1104.  Notice of Redemption.

     Notice of redemption shall be given by first-class mail, postage prepaid,
mailed not less than 30 nor more than 60 days prior to the Redemption Date, to
each Holder of Securities to be redeemed, at its address appearing in the
Security Register.

     All notices of redemption shall state:

          (1)  the Redemption Date,

          (2)  the Redemption Price,

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

                                      -52-

 
          (4) that on the Redemption Date the Redemption Price will become due
     and payable upon each such Security to be redeemed and, if applicable, that
     interest thereon will cease to accrue on and after said date,

          (5) the place or places where each such Security is to be surrendered
     for payment of the Redemption Price,

          (6) if applicable, the conversion price, that the date on which the
     right to convert the principal of the Securities or the portions thereof to
     be redeemed will terminate will be the Redemption Date and the place or
     places where such Securities may be surrendered for conversion, and

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

     Notice of redemption of Securities to be redeemed at the election of the
Company 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 and shall be irrevocable.

Section 1105.  Deposit of Redemption Price.

     Prior to 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,
segregate and hold in trust as provided in Section 1003) an amount of money
sufficient to pay the Redemption Price of, and (except if the Redemption Date
shall be an Interest Payment Date) accrued interest on, all the Securities 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, and from and after such date (unless the
Company shall default in the payment of the Redemption Price and accrued
interest) such Securities shall cease to bear interest. Upon surrender of any
such Security for redemption in accordance with said notice, such Security shall
be paid by the Company at the Redemption Price, together with accrued interest
to the Redemption Date; provided, however, that, unless otherwise specified as
contemplated by Section 301, instalments of interest whose Stated Maturity is on
or prior to the Redemption Date will 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 Security called for redemption shall not be so paid upon surrender
thereof for redemption, the principal and any premium shall, until paid, bear
interest from the Redemption Date at the rate prescribed therefor in the
Security.

Section 1107.  Securities Redeemed in Part.

     Any Security which is to be redeemed only in part 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

                                      -53-

 
in form satisfactory to the Company and the Trustee duly executed by, the Holder
thereof or its 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
and of like tenor, 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 any series except as otherwise specified as
contemplated by Section 301 for such Securities.

     The minimum amount of any sinking fund payment provided for by the terms of
any Securities 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 is herein referred to as an "optional sinking fund payment". If
provided for by the terms of any Securities, the cash amount of any sinking fund
payment may be subject to reduction as provided in Section 1202. Each sinking
fund payment shall be applied to the redemption of Securities as provided for by
the terms of such Securities.

Section 1202.  Satisfaction of Sinking Fund Payments with Securities.

     The Company (1) may deliver Outstanding Securities of a series (other than
any previously called for redemption) and (2) may apply as a credit Securities
of a 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, in each
case in satisfaction of all or any part of any sinking fund payment with respect
to any Securities of such series required to be made pursuant to the terms of
such Securities as and to the extent provided for by the terms of such
Securities; provided that the Securities to be so credited have not been
previously so credited. The Securities to be so credited shall be received and
credited for such purpose by the Trustee at the Redemption Price, as specified
in the Securities so to be redeemed, for redemption through operation of the
sinking fund and the amount of such 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 any
Securities, the Company will deliver to the Trustee an Officers' Certificate
specifying the amount of the next ensuing sinking fund payment for such
Securities pursuant to the terms of such Securities, the portion thereof, if
any, which is to be satisfied by payment of cash and the portion thereof, if
any, which is to be satisfied by delivering and crediting Securities pursuant to
Section 1202 and will also deliver to the Trustee any Securities to be so
delivered. Not less than 30 days prior to each such sinking fund payment date,
the Trustee shall select the Securities to be redeemed upon such sinking fund
payment date in the manner

                                      -54-

 
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

                      Defeasance and Covenant Defeasance

Section 1301.  Company's Option to Effect Defeasance or Covenant Defeasance.

     The Company may elect, at its option at any time, to have Section 1302 or
Section 1303 applied to any Securities or any series of Securities, as the case
may be, designated pursuant to Section 301 as being defeasible pursuant to such
Section 1302 or 1303, in accordance with any applicable requirements provided
pursuant to Section 301 and upon compliance with the conditions set forth below
in this Article. Any such election shall be evidenced by a Board Resolution or
in another manner specified as contemplated by Section 301 for such Securities.

Section 1302.  Defeasance and Discharge.

     Upon the Company's exercise of its option (if any) to have this Section
applied to any Securities or any series of Securities, as the case may be, the
Company shall be deemed to have been discharged from its obligations, and the
provisions of Article Fifteen shall cease to be effective, with respect to such
Securities as provided in this Section on and after the date the conditions set
forth in Section 1304 are satisfied (hereinafter called "Defeasance"). For this
purpose, such Defeasance means that the Company shall be deemed to have paid and
discharged the entire indebtedness represented by such Securities and to have
satisfied all its other obligations under such Securities and this Indenture
insofar as such Securities are concerned (and the Trustee, at the expense of the
Company, shall execute proper instruments acknowledging the same), subject to
the following which shall survive until otherwise terminated or discharged
hereunder: (1) the rights of Holders of such Securities to receive, solely from
the trust fund described in Section 1304 and as more fully set forth in such
Section, payments in respect of the principal of and any premium and interest on
such Securities when payments are due, (2) the Company's obligations with
respect to such Securities under Sections 304, 305, 306, 1002 and 1003, (3) the
rights, powers, trusts, duties and immunities of the Trustee hereunder and (4)
this Article. Subject to compliance with this Article, the Company may exercise
its option (if any) to have this Section applied to any Securities
notwithstanding the prior exercise of its option (if any) to have Section 1303
applied to such Securities.

Section 1303.  Covenant Defeasance.

     Upon the Company's exercise of its option (if any) to have this Section
applied to any Securities or any series of Securities, as the case may be, (1)
the Company shall be released from its obligations under Section 801(3),
Sections 1006 through 1007, inclusive, and any covenants provided pursuant to
Section 301(19), 901(2) or 901(7) for the benefit of the Holders of such
Securities and (2) the occurrence of any event specified in Sections 501(4)
(with respect to any of Section 801(3), Sections 1006 through 1007, inclusive,
and any such covenants provided pursuant to Section 301(19), 901(2) or 901(7)),
501(5) and 501(8) shall be deemed not to be or result in an Event of Default,
and (3)

                                      -55-

 
the provisions of Article Fifteen shall cease to be effective, in each case with
respect to such Securities as provided in this Section on and after the date the
conditions set forth in Section 1304 are satisfied (hereinafter called "Covenant
Defeasance"). For this purpose, such Covenant Defeasance means that, with
respect to such Securities, 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 specified Section (to the extent so specified in the case of Section
501(4)) or Article Fifteen, whether directly or indirectly by reason of any
reference elsewhere herein to any such Section or Article or by reason of any
reference in any such Section or Article to any other provision herein or in any
other document, but the remainder of this Indenture and such Securities shall be
unaffected thereby.

Section 1304.  Conditions to Defeasance or Covenant Defeasance.

     The following shall be the conditions to the application of Section 1302 or
Section 1303 to any Securities or any series of Securities, as the case may be:

          (1) The Company shall irrevocably have deposited or caused to be
     deposited with the Trustee (or another trustee which satisfies the
     requirements contemplated by Section 609 and agrees to comply with the
     provisions of this Article 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 benefits of the Holders of such
     Securities, (A) money in an amount, or (B) U.S. Government Obligations
     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, money in an amount, or (C) a
     combination thereof, in each case 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 any such other
     qualifying trustee) to pay and discharge, the principal of and any premium
     and interest on such Securities on the respective Stated Maturities, in
     accordance with the terms of this Indenture and such Securities. As used
     herein, "U.S. Government Obligation" means (x) any security which is (i) a
     direct obligation of the United States of America for the payment of which
     the full faith and credit of the United States of America is pledged or
     (ii) an obligation of a Person controlled or supervised by and acting as an
     agency or instrumentality of the United States of America the payment of
     which is unconditionally guaranteed as a full faith and credit obligation
     by the United States of America, which, in either case (i) or (ii), is not
     callable or redeemable at the option of the issuer thereof, and (y) any
     depositary receipt issued by a bank (as defined in Section 3(a)(2) of the
     Securities Act) as custodian with respect to any U.S. Government Obligation
     which is specified in Clause (x) above and held by such bank for the
     account of the holder of such depositary receipt, or with respect to any
     specific payment of principal of or interest on any U.S. Government
     Obligation which is so specified and held, 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 depositary receipt from any
     amount received by the custodian in respect of the U.S. Government
     Obligation or the specific payment of principal or interest evidenced by
     such depositary receipt.

          (2) In the event of an election to have Section 1302 apply to any
     Securities or any series of Securities, as the case may be, the Company
     shall have delivered to the Trustee an Opinion of Counsel stating that (A)
     the Company has received from, or there has been

                                      -56-

 
     published by, the Internal Revenue Service a ruling or (B) since the date
     of this instrument, there has been a change in the applicable Federal
     income tax law, in either case (A) or (B) to the effect that, and based
     thereon such opinion shall confirm that, the Holders of such Securities
     will not recognize gain or loss for Federal income tax purposes as a result
     of the deposit, Defeasance and discharge to be effected with respect to
     such Securities and will be subject to Federal income tax on the same
     amount, in the same manner and at the same times as would be the case if
     such deposit, Defeasance and discharge were not to occur.

          (3) In the event of an election to have Section 1303 apply to any
     Securities or any series of Securities, as the case may be, the Company
     shall have delivered to the Trustee an Opinion of Counsel to the effect
     that the Holders of such Securities will not recognize gain or loss for
     Federal income tax purposes as a result of the deposit and Covenant
     Defeasance to be effected with respect to such Securities and will be
     subject to Federal income tax on the same amount, in the same manner and at
     the same times as would be the case if such deposit and Covenant Defeasance
     were not to occur.

          (4) The Company shall have delivered to the Trustee an Officer's
     Certificate to the effect that neither such Securities nor any other
     Securities of the same series, if then listed on any securities exchange,
     will be delisted as a result of such deposit.

          (5) No event which is, or after notice or lapse of time or both would
     become, an Event of Default with respect to such Securities or any other
     Securities shall have occurred and be continuing at the time of such
     deposit or, with regard to any such event specified in Sections 501(6) and
     (7), at any time on or prior to the 90th day after the date of such deposit
     (it being understood that this condition shall not be deemed satisfied
     until after such 90th day).

          (6) Such Defeasance or Covenant Defeasance shall not cause the Trustee
     to have a conflicting interest within the meaning of the Trust Indenture
     Act (assuming all Securities are in default within the meaning of such
     Act).

          (7) Such Defeasance or Covenant Defeasance shall not result in a
     breach or violation of, or constitute a default under, any other agreement
     or instrument to which the Company is a party or by which it is bound.

          (8) Such Defeasance or Covenant Defeasance shall not result in the
     trust arising from such deposit constituting an investment company within
     the meaning of the Investment Company Act unless such trust shall be
     registered under such Act or exempt from registration thereunder.

          (9) At the time of such deposit, (A) no default in the payment of any
     principal of or premium or interest on any Senior Debt shall have occurred
     and be continuing, (B) no event of default with respect to any Senior Debt
     shall have resulted in such Senior Debt becoming, and continuing to be, due
     and payable prior to the date on which it would otherwise have become due
     and payable (unless payment of such Senior Debt has been made or duly
     provided for), and (C) no other event of default with respect to any Senior
     Debt shall have occurred and be continuing permitting (after notice or
     lapse of time or both) the holders of such Senior Debt (or

                                      -57-

 
     a trustee on behalf of such holders) to declare such Senior Debt due and
     payable prior to the date on which it would otherwise have become due and
     payable.

          (10) The Company shall have delivered to the Trustee an Officer's
     Certificate and an Opinion of Counsel, each stating that all conditions
     precedent with respect to such Defeasance or Covenant Defeasance have been
     complied with.

Section 1305.  Deposited Money and U.S. Government Obligations to Be Held in
               Trust; Miscellaneous Provisions.

     Subject to the provisions of the last paragraph of Section 1003, all money
and U.S. Government Obligations (including the proceeds thereof) deposited with
the Trustee or other qualifying trustee (solely for purposes of this Section and
Section 1306, the Trustee and any such other trustee are referred to
collectively as the "Trustee") pursuant to Section 1304 in respect of any
Securities shall be held in trust and applied by the Trustee, in accordance with
the provisions of such Securities and this Indenture, to the payment, either
directly or through any such Paying Agent (including the Company acting as its
own Paying Agent) as the Trustee may determine, to the Holders of such
Securities, of all sums due and to become due thereon in respect of principal
and any premium and interest, but money so held in trust need not be segregated
from other funds except to the extent required by law. Money and U.S. Government
Obligations so held in trust shall not be subject to the provisions of Article
Fifteen.

     The Company shall pay and indemnify the Trustee against any tax, fee or
other charge imposed on or assessed against the U.S. Government Obligations
deposited pursuant to Section 1304 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 Outstanding Securities.

     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 U.S. Government Obligations held by it as provided in Section 1304 with
respect to any Securities 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 the Defeasance or Covenant Defeasance, as
the case may be, with respect to such Securities.

Section 1306.  Reinstatement.

     If the Trustee or the Paying Agent is unable to apply any money in
accordance with this Article with respect to any Securities by reason of any
order or judgment of any court or governmental authority enjoining, restraining
or otherwise prohibiting such application, then the obligations under this
Indenture and such Securities from which the Company has been discharged or
released pursuant to Section 1302 or 1303 shall be revived and reinstated as
though no deposit had occurred pursuant to this Article with respect to such
Securities, until such time as the Trustee or Paying Agent is permitted to apply
all money held in trust pursuant to Section 1305 with respect to such Securities
in accordance with this Article; provided, however, that if the Company makes
any payment of principal of or any premium or interest on any such Security
following such reinstatement of its obligations, the Company shall be subrogated
to the rights (if any) of the Holders of such Securities to receive such payment
from the money so held in trust.

                                      -58-

 
                               ARTICLE FOURTEEN

                           Conversion of Securities

Section 1401.  Applicability of Article.

     The provisions of this Article shall be applicable to the Securities of any
series which are convertible into shares of Common Stock of the Company, and the
issuance of such shares of Common Stock upon the conversion of such Securities,
except as otherwise specified as contemplated by Section 301 for the Securities
of such series.

Section 1402.  Exercise of Conversion Privilege.

     In order to exercise a conversion privilege, the Holder of a Security of a
series with such a privilege shall surrender such Security to the Company at the
office or agency maintained for that purpose pursuant to Section 1002,
accompanied by a duly executed conversion notice to the Company substantially in
the form set forth in Section 206 stating that the Holder elects to convert such
Security or a specified portion thereof. Such notice shall also state, if
different from the name and address of such Holder, the name or names (with
address) in which the certificate or certificates for shares of Common Stock
which shall be issuable on such conversion shall be issued. Securities
surrendered for conversion shall (if so required by the Company or the Trustee)
be duly endorsed by or accompanied by instruments of transfer in forms
satisfactory to the Company and the Trustee duly executed by the registered
Holder or its attorney duly authorized in writing; and Securities so surrendered
for conversion (in whole or in part) during the period from the close of
business on any Regular Record Date to the opening of business on the next
succeeding Interest Payment Date (excluding Securities or portions thereof
called for redemption during such period) shall also be accompanied by payment
in funds acceptable to the Company of an amount equal to the interest payable on
such Interest Payment Date on the principal amount of such Security then being
converted, and such interest shall be payable to such registered Holder
notwithstanding the conversion of such Security, subject to the provisions of
Section 307 relating to the payment of Defaulted Interest by the Company. As
promptly as practicable after the receipt of such notice and of any payment
required pursuant to a Board Resolution 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 setting forth the
terms of such series of Security, and the surrender of such Security in
accordance with such reasonable regulations as the Company may prescribe, the
Company shall issue and shall deliver, at the office or agency at which such
Security is surrendered, to such Holder or on its written order, a certificate
or certificates for the number of full shares of Common Stock issuable upon the
conversion of such Security (or specified portion thereof), in accordance with
the provisions of such Board Resolution, Officers' Certificate or supplemental
indenture, and cash as provided therein in respect of any fractional share of
such Common Stock otherwise issuable upon such conversion. Such conversion shall
be deemed to have been effected immediately prior to the close of business on
the date on which such notice and such payment, if required, shall have been
received in proper order for conversion by the Company and such Security shall
have been surrendered as aforesaid (unless such Holder shall have so surrendered
such Security and shall have instructed the Company to effect the conversion on
a particular date following such surrender and such Holder shall be entitled to
convert such Security on such date, in which case such conversion shall be
deemed to be effected immediately prior to the close of business on such date)
and at such time the rights of the Holder of such Security as such Security
Holder shall cease and the person

                                      -59-

 
or persons in whose name or names any certificate or certificates for shares of
Common Stock of the Company shall be issuable upon such conversion shall be
deemed to have become the Holder or Holders of record of the shares represented
thereby. Except as set forth above and subject to the final paragraph of Section
307, no payment or adjustment shall be made upon any conversion on account of
any interest accrued on the Securities (or any part thereof) surrendered for
conversion or on account of any dividends on the Common Stock of the Company
issued upon such conversion.

     In the case of any Security which is converted in part only, upon such
conversion the Company shall execute and the Trustee shall authenticate and
deliver to or on the order of the Holder thereof, at the expense of the Company,
a new Security or Securities of the same series, of authorized denominations, in
aggregate principal amount equal to the unconverted portion of such Security.

Section 1403.  No Fractional Shares.

     No fractional share of Common Stock of the Company shall be issued upon
conversions of Securities of any series. If more than one Security shall be
surrendered for conversion at one time by the same Holder, the number of full
shares which shall be issuable upon conversion shall be computed on the basis of
the aggregate principal amount of the Securities (or specified portions thereof
to the extent permitted hereby) so surrendered. If, except for the provisions of
this Section 1403, any Holder of a Security or Securities would be entitled to a
fractional share of Common Stock of the Company upon the conversion of such
Security or Securities, or specified portions thereof, the Company shall pay to
such Holder an amount in cash equal to the current market value of such
fractional share computed, (i) if such Common Stock is listed or admitted to
unlisted trading privileges on a national securities exchange, on the basis of
the last reported sale price regular way on such exchange on the last trading
day prior to the date of conversion upon which such a sale shall have been
effected, or (ii) if such Common Stock is not at the time so listed or admitted
to unlisted trading privileges on a national securities exchange, on the basis
of the average of the bid and asked prices of such Common Stock in the over-the-
counter market, on the last trading day prior to the date of conversion, as
reported by the National Quotation Bureau, Incorporated or similar organization
if the National Quotation Bureau, Incorporated is no longer reporting such
information, or if not so available, the fair market price as determined by the
Board of Directors. For purposes of this Section, "trading day" shall mean each
Monday, Tuesday, Wednesday, Thursday and Friday other than any day on which the
Common Stock is not traded on the New York Stock Exchange, or if the Common
Stock is not traded on the New York Stock Exchange, on the principal exchange or
market on which the Common Stock is traded or quoted.

Section 1404.  Adjustment of Conversion Price.

     The conversion price of Securities of any series that is convertible into
Common Stock of the Company shall be adjusted for any stock dividends, stock
splits, reclassifications, combinations or similar transactions in accordance
with the terms of the supplemental indenture or Board Resolutions setting forth
the terms of the Securities of such series.

     Whenever the conversion price is adjusted, the Company shall compute the
adjusted conversion price in accordance with terms of the applicable Board
Resolution or supplemental indenture and shall prepare an Officers' Certificate
setting forth the adjusted conversion price and showing in reasonable detail the
facts upon which such adjustment is based, and such certificate shall forthwith
be filed at each office or agency maintained for the purpose of conversion of
Securities pursuant to Section 1002 and, if

                                      -60-

 
different, with the Trustee. The Company shall forthwith cause a notice setting
forth the adjusted conversion price to be mailed, first class postage prepaid,
to each Holder of Securities of such series at its address appearing on the
Security Register and to any conversion agent other than the Trustee.

Section 1405.  Notice of Certain Corporate Actions.

In case:

          (1) the Company shall declare a dividend (or any other distribution)
     on its Common Stock payable otherwise than in cash out of its retained
     earnings (other than a dividend for which approval of any shareholders of
     the Company is required); or

          (2) the Company shall authorize the granting to the holders of its
     Common Stock of rights, options or warrants to subscribe for or purchase
     any shares of capital stock of any class or of any other rights (other than
     any such grant for which approval of any shareholders of the Company is
     required); or

          (3) of any reclassification of the Common Stock of the Company (other
     than a subdivision or combination of its outstanding shares of Common
     Stock, or of any consolidation, merger or share exchange to which the
     Company is a party and for which approval of any shareholders of the
     Company is required), or of the sale of all or substantially all of the
     assets of the Company; or

          (4) of the voluntary or involuntary dissolution, liquidation or
     winding up of the Company;

then the Company shall cause to be filed with the Trustee, and shall cause to be
mailed to all Holders at their last addresses as they shall appear in the
Securities Register, at least 20 days (or 10 days in any case specified in
Clause (1) or (2) above) prior to the applicable record date hereinafter
specified, a notice stating (i) the date on which a record is to be taken for
the purpose of such dividend, distribution, rights, options or warrants, or, if
a record is not to be taken, the date as of which the holders of Common Stock of
record to be entitled to such dividend, distribution, rights, options or
warrants are to be determined, or (ii) the date on which such reclassification,
consolidation, merger, share exchange, sale, dissolution, liquidation or winding
up is expected to become effective, and the date as of which it is expected that
holders of Common Stock of record shall be entitled to exchange their shares of
Common Stock for securities, cash or other property deliverable upon such
reclassification, consolidation, merger, share exchange, sale, dissolution,
liquidation or winding up. If at any time the Trustee shall not be the
conversion agent, a copy of such notice shall also forthwith be filed by the
Company with the Trustee.

Section 1406.  Reservation of Shares of Common Stock.

     The Company shall at all times reserve and keep available, free from
preemptive rights, out of its authorized but unissued Common Stock, for the
purpose of effecting the conversion of Securities, the full number of shares of
Common Stock of the Company then issuable upon the conversion of all outstanding
Securities of any series that has conversion rights.

                                      -61-

 
Section 1407.  Payment of Certain Taxes Upon Conversion.

     The Company will pay any and all taxes that may be payable in respect of
the issue or delivery of shares of its Common Stock on conversion of Securities
pursuant hereto. The Company shall not, however, be required to pay any tax
which may be payable in respect of any transfer involved in the issue and
delivery of shares of its Common Stock in a name other than that of the Holder
of the Security or Securities to be converted, and no such issue or delivery
shall be made unless and until the person requesting such issue has paid to the
Company the amount of any such tax, or has established, to the satisfaction of
the Company, that such tax has been paid.

Section 1408.  Nonassessability.

     The Company covenants that all shares of its Common Stock which may be
issued upon conversion of Securities will upon issue in accordance with the
terms hereof be duly and validly issued and fully paid and nonassessable.

Section 1409.  Effect of Consolidation or Merger on Conversion Privilege.

     In case of any consolidation of the Company with, or merger of the Company
into or with any other Person, or in case of any sale of all or substantially
all of the assets of the Company, the Company or the Person formed by such
consolidation or the Person into which the Company shall have been merged or the
Person which shall have acquired such assets, as the case may be, shall execute
and deliver to the Trustee a supplemental indenture providing that the Holder of
each Security then outstanding of any series that is convertible into Common
Stock of the Company shall have the right, which right shall be the exclusive
conversion right thereafter available to said Holder (until the expiration of
the conversion right of such Security), to convert such Security into the kind
and amount of shares of stock or other securities or property (including cash)
receivable upon such consolidation, merger or sale by a holder of the number of
shares of Common Stock of the Company into which such Security might have been
converted immediately prior to such consolidation, merger or sale, subject to
compliance with the other provisions of this Indenture, such Security and such
supplemental indenture. Such supplemental indenture shall provide for
adjustments which shall be as nearly equivalent as may be practicable to the
adjustments provided for in such Security. The above provisions of this Section
shall similarly apply to successive consolidations, mergers or sales. It is
expressly agreed and understood that anything in this Indenture to the contrary
notwithstanding, if, pursuant to such merger, consolidation or sale, holders of
outstanding shares of Common Stock of the Company do not receive shares of
common stock of the surviving corporation but receive other securities, cash or
other property or any combination thereof, Holders of Securities shall not have
the right to thereafter convert their Securities into common stock of the
surviving corporation or the corporation which shall have acquired such assets,
but rather, shall have the right upon such conversion to receive the other
securities, cash or other property receivable by a holder of the number of
shares of Common Stock of the Company into which the Securities held by such
holder might have been converted immediately prior to such consolidation, merger
or sale, all as more fully provided in the first sentence of this Section 1409.
Anything in this Section 1409 to the contrary notwithstanding, the provisions of
this Section 1409 shall not apply to a merger or consolidation of another
corporation with or into the Company pursuant to which both of the following
conditions are applicable: (i) the Company is the surviving corporation and (ii)
the outstanding shares of Common Stock of the Company are not changed or
converted into any

                                      -62-

 
other securities or property (including cash) or changed in number or character
or reclassified pursuant to the terms of such merger or consolidation.

     As evidence of the kind and amount of shares of stock or other securities
or property (including cash) into which Securities may properly be convertible
after any such consolidation, merger or sale, or as to the appropriate
adjustments of the conversion prices applicable with respect thereto, the
Trustee shall be furnished with and may accept the certificate or opinion of an
independent certified public accountant with respect thereto; and, in the
absence of bad faith on the part of the Trustee, the Trustee may conclusively
rely thereon, and shall not be responsible or accountable to any Holder of
Securities for any provision in conformity therewith or approved by such
independent certified accountant which may be contained in said supplemental
indenture.

Section 1410.  Duties of Trustee Regarding Conversion.

     Neither the Trustee nor any conversion agent shall at any time be under any
duty or responsibility to any Holder of Securities of any series that is
convertible into Common Stock of the Company to determine whether any facts
exist which may require any adjustment of the conversion price, or with respect
to the nature or extent of any such adjustment when made, or with respect to the
method employed, whether herein or in any supplemental indenture, any
resolutions of the Board of Directors or written instrument executed by one or
more officers of the Company provided to be employed in making the same. Neither
the Trustee nor any conversion agent shall be accountable with respect to the
validity or value (or the kind or amount) of any shares of Common Stock of the
Company, or of any securities or property, which may at any time be issued or
delivered upon the conversion of any Securities and neither the Trustee nor any
conversion agent makes any representation with respect thereto. Subject to the
provisions of Section 601, neither the Trustee nor any conversion agent shall be
responsible for any failure of the Company to issue, transfer or deliver any
shares of its Common Stock or stock certificates or other securities or property
upon the surrender of any Security for the purpose of conversion or to comply
with any of the covenants of the Company contained in this Article Fourteen or
in the applicable supplemental indenture, resolutions of the Board of Directors
or written instrument executed by one or more duly authorized officers of the
Company.

Section 1411.  Repayment of Certain Funds Upon Conversion.

     Any funds which at any time shall have been deposited by the Company or on
its behalf with the Trustee or any other paying agent for the purpose of paying
the principal of, and premium, if any, and interest, if any, on any of the
Securities (including funds deposited for the sinking fund referred to in
Article Twelve hereof) and which shall not be required for such purposes because
of the conversion of such Securities as provided in this Article Fourteen shall
after such conversion be repaid to the Company by the Trustee upon the Company's
written request.

                                      -63-

 
                                ARTICLE FIFTEEN

                          Subordination of Securities

Section 1501.  Securities Subordinate to Senior Debt.

     Except as otherwise provided in a supplemental indenture or pursuant to
Section 301 the Company covenants and agrees, and each Holder of a Security, by
its acceptance thereof, likewise covenants and agrees, that, to the extent and
in the manner hereinafter set forth in this Article, the indebtedness
represented by the Securities and the payment of the principal of and any
premium and interest on each and all of the Securities are hereby expressly made
subordinate and subject in right of payment to the prior payment in full of all
Senior Debt.

Section 1502.  Payment Over of Proceeds Upon Dissolution, Etc.

     In the event of (a) any insolvency or bankruptcy case or proceeding, or any
receivership, liquidation, reorganization, debt restructuring or other similar
case or proceeding in connection therewith, relative to the Company or to its
creditors, as such, or to its assets, or (b) any liquidation, dissolution or
other winding up of the Company, whether voluntary or involuntary and whether or
not involving insolvency or bankruptcy, or (c) any assignment for the benefit of
creditors or any other marshalling of assets and liabilities of the Company,
then and in any such event the holders of Senior Debt shall be entitled to
receive payment in full of all amounts due or to become due on or in respect of
all Senior Debt, or provision shall be made for such payment in money or money's
worth, before the Holders of the Securities are entitled to receive any payment
on account of principal of or any premium or interest on the Securities, and to
that end the holders of Senior Debt or their representative or representatives
or the trustee or trustees under any indenture under which any instruments
evidencing any of such Senior Debt may have been issued shall be entitled to
receive, for application to the payment thereof, any payment or distribution of
any kind or character, whether in cash, property or securities, which may be
payable or deliverable in respect of the Securities in any such case,
proceeding, dissolution, liquidation or other winding up or event, to the extent
necessary to pay all Senior Debt in full, after giving effect to any concurrent
payment or distribution to or for the holders of Senior Debt.

     In the event that, notwithstanding the foregoing provisions of this
Section, the Trustee or the Holder of any Security shall have received any
payment or distribution of assets of the Company of any kind or character,
whether in cash, property or securities, before all Senior Debt is paid in full
or payment thereof provided for, [and if such fact shall, at or prior to the
time of such payment or distribution, have been made known to the Trustee or, as
the case may be, such Holder,] then and in such event such payment or
distribution shall be paid over or delivered forthwith to the trustee in
bankruptcy, receiver, liquidating trustee, custodian, assignee, agent or other
Person making payment or distribution of assets of the Company for application
to the payment of all Senior Debt remaining unpaid, to the extent necessary to
pay all Senior Debt in full, after giving effect to any concurrent payment or
distribution to or for the holders of Senior Debt.

     For purposes of this Article only, the words "cash, property or securities"
shall not be deemed to include shares of stock of the Company as reorganized or
readjusted, or securities of the Company or any other corporation provided for
by a plan of reorganization or readjustment which are subordinated

                                      -64-

 
in right of payment to all Senior Debt which may at the time be outstanding to
substantially the same extent as, or to a greater extent than, the Securities
are so subordinated as provided in this Article. The consolidation of the
Company with, or the merger of the Company into, another Person or the
liquidation or dissolution of the Company following the conveyance or transfer
of its properties and assets substantially as an entirety to another Person upon
the terms and conditions set forth in Article Eight shall not be deemed a
dissolution, winding up, liquidation, reorganization, assignment for the benefit
of creditors or marshalling of assets and liabilities of the Company for the
purposes of this Section if the Person formed by such consolidation or into
which the Company is merged or which acquires by conveyance or transfer such
properties and assets substantially as an entirety, as the case may be, shall,
as a part of such consolidation, merger, conveyance or transfer, comply with the
conditions set forth in Article Eight.

Section 1503.  Prior Payment to Senior Debt Upon Acceleration of Securities.

     In the event that any Securities are declared due and payable before their
Stated Maturity, then and in such event the holders of the Senior Debt
outstanding at the time such Securities so become due and payable shall be
entitled to receive payment in full of all amounts due or to become due on or in
respect of all Senior Debt, or provision shall be made for such payment in money
or money's worth before the Holders of the Securities are entitled to receive
any payment by the Company on account of the principal of or any premium or
interest on the Securities or on account of the purchase or other acquisition of
Securities; provided, however, that nothing in this Section shall prevent the
satisfaction of any sinking fund payment in accordance with Article Twelve by
delivering and crediting pursuant to Section 1202 Securities which have been
acquired (upon redemption or otherwise) prior to such declaration of
acceleration or which have been converted pursuant to Article Fourteen.

     In the event that, notwithstanding the foregoing, the Company shall make
any payment to the Trustee or the Holder of any Security prohibited by the
foregoing provisions of this Section, and if such fact shall, at or prior to the
time of such payment, have been made known to the Trustee or, as the case may
be, such Holder, then and in such event such payment shall be paid over and
delivered forthwith to the Company.

     The provisions of this Section shall not apply to any payment with respect
to which Section 1502 would be applicable.

Section 1504.  No Payment When Senior Debt in Default.

          (a) In the event and during the continuation of any default in the
     payment of principal of or any premium or interest on any Senior Debt
     during or beyond any applicable grace period with respect thereto, or in
     the event that any default with respect to any Senior Debt shall have
     occurred and be continuing permitting the holders of such Senior Debt (or a
     trustee on behalf of the holders thereof) to declare such Senior Debt due
     and payable prior to the date on which it would otherwise have become due
     and payable, unless and until such default shall have been cured or waived
     or shall have ceased to exist and, if any such Senior Debt shall have been
     accelerated, such acceleration shall have been rescinded or annulled, or
     (b) in the event any judicial proceeding shall be pending with respect to
     any such default, then no payment shall be made by the Company on account
     of principal of or any premium or interest on the Securities or on account
     of the purchase or other acquisition of Securities; provided, however, that
     nothing

                                      -65-

 
     in this Section shall prevent the satisfaction of any sinking fund payment
     in accordance with Article Twelve by delivering and crediting pursuant to
     Section 1202 Securities which have been acquired (upon redemption or
     otherwise) prior to such declaration of acceleration or which have been
     converted pursuant to Article Fourteen.

     In the event that, notwithstanding the foregoing, the Company shall make
any payment to the Trustee or the Holder of any Security prohibited by the
foregoing provisions of this Section, and if such fact shall, at or prior to the
time of such payment, have been made known to the Trustee or, as the case may
be, such Holder, then and in such event such payment shall be paid over and
delivered forthwith to the Company.

     The provisions of this Section shall not apply to any payment with respect
to which Section 1502 would be applicable.

Section 1505.  Payment Permitted If No Default.

     Nothing contained in this Article or elsewhere in this Indenture or in any
of the Securities shall prevent (a) the Company, at any time except during the
pendency of any case, proceeding, dissolution, liquidation or other winding up,
debt restructuring, assignment for the benefit of creditors or other marshalling
of assets and liabilities of the Company referred to in Section 1502 or under
the conditions described in Section 1503 or 1504, from making payments at any
time of principal of and any premium or interest on the Securities, or (b) the
application by the Trustee of any money deposited with it hereunder to the
payment of or on account of the principal of and any premium or interest on the
Securities or the retention of such payment by the Holders, if, at the time of
such application by the Trustee, it did not have knowledge that such payment
would have been prohibited by the provisions of this Article.

Section 1506.  Subrogation to Rights of Holders of Senior Debt.

     Subject to the payment in full of all Senior Debt, the Holders of the
Securities shall be subrogated to the rights of the holders of such Senior Debt
to receive payments and distributions of cash, property and securities
applicable to the Senior Debt until the principal of and any premium and
interest on the Securities shall be paid in full. For purposes of such
subrogation, no payments or distributions to the holders of the Senior Debt of
any cash, property or securities to which the Holders of the Securities or the
Trustee would be entitled except for the provisions of this Article, and no
payments over pursuant to the provisions of this Article to the holders of
Senior Debt by Holders of the Securities or the Trustee, shall, as among the
Company, its creditors other than holders of Senior Debt and the Holders of the
Securities, be deemed to be a payment or distribution by the Company to or on
account of the Senior Debt.

Section 1507. Provisions Solely to Define Relative Rights.

     The provisions of this Article are and are intended solely for the purpose
of defining the relative rights of the Holders of the Securities on the one hand
and the holders of Senior Debt on the other hand. Nothing contained in this
Article or elsewhere in this Indenture or in the Securities is intended to or
shall (a) impair, as among the Company, its creditors other than holders of
Senior Debt and the Holders of the Securities, the obligation of the Company,
which is absolute and unconditional (and which,

                                      -66-

 
subject to the rights under this Article of the holders of Senior Debt, is
intended to rank equally with all other general obligations of the Company), to
pay to the Holders of the Securities the principal of and any premium and
interest on the Securities as and when the same shall become due and payable in
accordance with their terms; or (b) affect the relative rights against the
Company of the Holders of the Securities and creditors of the Company other than
the holders of Senior Debt; or (c) prevent the Trustee or the Holder of any
Security from exercising all remedies otherwise permitted by applicable law upon
default under this Indenture, subject to the rights, if any, under this Article
of the holders of Senior Debt to receive cash, property and securities otherwise
payable or deliverable to the Trustee or such Holder.

Section 1508.  Trustee to Effectuate Subordination.

     Each Holder of a Security by its acceptance thereof authorizes and directs
the Trustee on its behalf to take such action as may be necessary or appropriate
to effectuate the subordination provided in this Article and appoints the
Trustee its attorney-in-fact for any and all such purposes.

Section 1509.  No Waiver of Subordination Provisions.

     No right of any present or future holder of any Senior Debt to enforce
subordination as herein provided shall at any time in any way be prejudiced or
impaired by any act or failure to act on the part of the Company or by any act
or failure to act, in good faith, by any such holder, or by any non-compliance
by the Company with the terms, provisions and covenants of this Indenture,
regardless of any knowledge thereof any such holder may have or be otherwise
charged with.

     Without in any way limiting the generality of the foregoing paragraph, the
holders of Senior Debt may, at any time and from time to time, without the
consent of or notice to the Trustee or the Holders of the Securities, without
incurring responsibility to the Holders of the Securities and without impairing
or releasing the subordination provided in this Article or the obligations
hereunder of the Holders of the Securities to the holders of Senior Debt, do any
one or more of the following: (i) change the manner, place or terms of payment
or extend the time of payment of, or renew or alter, Senior Debt, or otherwise
amend or supplement in any manner Senior Debt or any instrument evidencing the
same or any agreement under which Senior Debt is outstanding; (ii) sell,
exchange, release or otherwise dispose of any property pledged, mortgaged or
otherwise securing Senior Debt; (iii) release any Person liable in any manner
for the collection of Senior Debt; and (iv) exercise or refrain from exercising
any rights against the Company and any other Person.

Section 1510.  Notice to Trustee.

     The Company shall give prompt written notice to the Trustee of any fact
known to the Company which would prohibit the making of any payment to or by the
Trustee in respect of the Securities. Notwithstanding the provisions of this
Article or any other provision of this Indenture, the Trustee shall not be
charged with knowledge of the existence of any facts which would prohibit the
making of any payment to or by the Trustee in respect of the Securities, unless
and until the Trustee shall have received written notice thereof from the
Company or a holder of Senior Debt or from any trustee therefor; and, prior to
the receipt of any such written notice, the Trustee, subject to the provisions
of Section 601, shall be entitled in all respects to assume that no such facts
exist; provided, however, that if the Trustee shall not have received the notice
provided for in this Section at least two

                                      -67-

 
Business Days prior to the date upon which by the terms hereof any money may
become payable for any purpose (including, without limitation, the payment of
the principal of and any premium or interest on any Security), then, anything
herein contained to the contrary notwithstanding, the Trustee shall have full
power and authority to receive such money and to apply the same to the purpose
for which such money was received and shall not be affected by any notice to the
contrary which may be received by it within two Business Days prior to such
date.

     Subject to the provisions of Section 601, the Trustee shall be entitled to
rely on the delivery to it of a written notice by a Person representing himself
to be a holder of Senior Debt (or a trustee therefor) to establish that such
notice has been given by a holder of Senior Debt (or a trustee therefor). In the
event that the Trustee determines in good faith that further evidence is
required with respect to the right of any Person as a holder of Senior Debt to
participate in any payment or distribution pursuant to this Article, the Trustee
may request such Person to furnish evidence to the reasonable satisfaction of
the Trustee as to the amount of Senior Debt held by such Person, the extent to
which such Person is entitled to participate in such payment or distribution and
any other facts pertinent to the rights of such Person under this Article, and
if such evidence is not furnished, the Trustee may defer any payment to such
Person pending judicial determination as to the right of such Person to receive
such payment.

Section 1511.  Reliance on Judicial Order or Certificate of Liquidating Agent.

     Upon any payment or distribution of assets of the Company referred to in
this Article, the Trustee, subject to the provisions of Section 601, and the
Holders of the Securities shall be entitled to rely upon any order or decree
entered by any court of competent jurisdiction in which such insolvency,
bankruptcy, receivership, liquidation, reorganization, dissolution, winding up
or similar case or proceeding is pending, or a certificate of the trustee in
bankruptcy, receiver, liquidating trustee, custodian, assignee for the benefit
of creditors, agent or other Person making such payment or distribution,
delivered to the Trustee or to the Holders of Securities, for the purpose of
ascertaining the Persons entitled to participate in such payment or
distribution, the holders of the Senior Debt and other indebtedness of the
Company, the amount thereof or payable thereon, the amount or amounts paid or
distributed thereon and all other facts pertinent thereto or to this Article.

Section 1512.  Trustee Not Fiduciary for Holders of Senior Debt.

     The Trustee, in its capacity as trustee under this Indenture, shall not be
deemed to owe any fiduciary duty to the holders of Senior Debt and shall not be
liable to any such holders if it shall in good faith mistakenly pay over or
distribute to Holders of Securities or to the Company or to any other Person
cash, property or securities to which any holders of Senior Debt shall be
entitled by virtue of this Article or otherwise.

Section 1513.  Rights of Trustee as Holder of Senior Debt; Preservation of
               Trustee's Rights.

     The Trustee in its individual capacity shall be entitled to all the rights
set forth in this Article with respect to any Senior Debt which may at any time
be held by it, to the same extent as any other holder of Senior Debt, and
nothing in this Indenture shall deprive the Trustee of any of its rights as such
holder.

                                      -68-

 
     Nothing in this Article shall apply to claims of, or payments to, the
Trustee under or pursuant to Section 607.

Section 1514.  Article Applicable to Paying Agents.

     In case at any time any Paying Agent other than the Trustee shall have been
appointed by the Company and be then acting hereunder, the term "Trustee" as
used in this Article shall in such case (unless the context otherwise requires)
be construed as extending to and including such Paying Agent within its meaning
as fully for all intents and purposes as if such Paying Agent were named in this
Article in addition to or in place of the Trustee; provided, however, that
Section 1513 shall not apply to the Company or any Affiliate of the Company if
it or such Affiliate acts as Paying Agent.

Section 1515.  Certain Conversions Deemed Payment.

     For the purposes of this Article only, (1) the issuance and delivery of
junior securities upon conversion of Securities in accordance with Article
Fourteen shall not be deemed to constitute a payment or distribution on account
of the principal of or any premium or interest on Securities or on account of
the purchase or other acquisition of Securities, and (2) the payment, issuance
or delivery of cash, property or securities (other than junior securities) upon
conversion of a Security shall be deemed to constitute payment on account of the
principal of such Security. For the purposes of this Section, the term "junior
securities" means (a) shares of any stock of any class of the Company and (b)
securities of the Company which are subordinated in right of payment to all
Senior Debt which may be outstanding at the time of issuance or delivery of such
securities to substantially the same extent as, or to a greater extent than, the
Securities are so subordinated as provided in this Article.

Section 1516.  Obligations of Company and Right to Convert Unconditional.

     Nothing contained in this Article or elsewhere in this Indenture or in the
Securities is intended to or shall impair, as among the Company, its creditors
other than holders of Senior Debt and the Holders of the Securities, the
obligation of the Company, which is absolute and unconditional, to pay to the
Holders of the Securities the principal of and any premium and interest on the
Securities as and when the same shall become due and payable in accordance with
their terms, or affect the relative rights of the Holders of the Securities and
creditors of the Company other than the holders of Senior Debt, nor shall
anything herein or therein prevent the Trustee or the Holder of any Securities
from exercising all remedies otherwise permitted by applicable law upon default
under this Indenture, subject to the rights, if any, under this Article of the
holders of Senior Debt in respect of cash, property or securities of the Company
received upon the exercise of any such remedy.

     Nothing contained in this Article or elsewhere in this Indenture or in the
Securities is intended to or shall impair, as among the Company, its creditors
other than holders of Senior Debt and the Holders of the Securities, the right,
which is absolute and unconditional, of the Holder of any Security to convert
such Security in accordance with Article Fourteen.

                         _____________________________

                                      -69-

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

     In Witness Whereof, the parties hereto have caused this Indenture to be
duly executed, and their respective corporate seals to be hereunto affixed and
attested, all as of the day and year first above written.

                                    Armstrong World Industries, Inc.

                                        /s/ E. Follin Smith
                                    By  __________________________
                                        E. Follin Smith
                                        Vice President and Treasurer

Attest:

/s/ Robert J. Sandkuhler
________________________________

                                    The First National Bank of Chicago

                                        /s/ Michael D. Pinzon
                                    By  __________________________
                                    
 
 

Attest:

Mary R. Fonti
________________________________
Authorized Officer

                                      -70-

 
State of New York            )
                             )  (S).:
County of New York           )

     On the 23rd day of December, 1998, before me personally came Michael
Pinzon, to me known, who, being by me duly sworn, did depose and say that he/she
is a Officer of The First National Bank of Chicago, one of the corporations
described in and which executed the foregoing instrument; that she knows the
seal of said corporation; that the seal affixed to said instrument is such
corporate seal; that it was so affixed by authority of the Board of Directors of
said corporation; and that she signed her name thereto by like authority.

                                                       /s/ Mark E. Davis
                                                       -------------------------


Commonwealth of Pennsylvania )
                             )  (S).:
County of Lancaster          )

     On the 23rd day of December, 1998, before me personally came E. Follin
Smith, to me known, who, being by me duly sworn, did depose and say that she is
Treasurer of Armstrong World Industries, Inc., one of the corporations described
in and which executed the foregoing instrument; that she knows the seal of said
corporation; that the seal affixed to said instrument is such corporate seal;
that it was so affixed by authority of the Board of Directors of said
corporation; and that she signed his or her name thereto by like authority.

                                                     /s/ Donna L. Royer-Good
                                                     -------------------------

                                      -71-