WISCONSIN POWER AND LIGHT COMPANY


                              OFFICERS' CERTIFICATE


                          Dated as of October 27, 1998


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


               Setting Forth Terms of a Series of Debt Securities


                      5.70% Debentures Due October 15, 2008


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


                            Pursuant to the Indenture
                            Dated as of June 20, 1997






                              OFFICERS' CERTIFICATE

         The undersigned,  the Vice  President-Treasurer and Corporate Secretary
and the Assistant  Treasurer of Wisconsin  Power and Light Company,  a Wisconsin
corporation  (the  "Company"),  hereby  certify as  provided  below  pursuant to
Section  2.01 of the  Indenture,  dated as of June 20,  1997 (the  "Indenture"),
between the Company and Firstar Trust Company (subsequently succeeded by Firstar
Bank Milwaukee, N.A.) (the "Trustee").  This Officers' Certificate is delivered,
pursuant to authority granted to the undersigned by resolutions adopted on April
21, 1998 by the Board of Directors  of the Company,  for the purpose of creating
and setting forth the terms of a series of  Securities to be issued  pursuant to
the  Indenture.  Capitalized  terms not  otherwise  defined  herein  are used as
defined in the Indenture.

         1. The Board of Directors of the Company has authorized the creation by
the  Company  of the  series of  Securities  described  below  pursuant  to this
Officers' Certificate and in accordance with the Indenture.

         2. The title of the Securities  shall be "5.70%  Debentures due October
15, 2008" (herein called the "Debentures").

         3.  The  aggregate   principal   amount  of  Debentures  which  may  be
authenticated and delivered under the Indenture is limited to U.S.  $60,000,000,
except for Debentures  authenticated and delivered upon registration of transfer
of, or in exchange for, or in lieu of, other  Debentures as provided in Sections
2.07,  2.08,  2.13 or 9.06 of the  Indenture  and except for  Debentures  which,
pursuant  to  Section  2.02 of the  Indenture,  are  deemed  never to have  been
authenticated and delivered thereunder.

         4. The principal of the Debentures  shall be payable in U.S. dollars on
October 15, 2008.

         5. The  Debentures  shall bear interest at the rate of 5.70% per annum;
such  interest  shall  accrue  from  October  30,  1998 (or from the most recent
interest  payment  date to which  interest  on the  Debentures  has been paid or
provided  for);  the  interest  payment  dates on which such  interest  shall be
payable  shall be April 15 and  October  15 in each year,  commencing  April 15,
1999;  the record  dates for the  determination  of Holders to whom  interest is
payable shall be the April 1 or October 1 next preceding  each interest  payment
date. Interest on the Debentures shall be payable in U.S. dollars.

         6.  Pursuant to the  Indenture,  the Trustee has been  appointed as the
Registrar for the  Debentures.  The Trustee is hereby  further  appointed as the
initial Paying Agent and Transfer Agent of the Debentures.  The principal of and
interest on the  Debentures  shall be payable at the office of the Paying Agent,
which shall initially be located in Milwaukee, Wisconsin.

         7. The Debentures shall not be redeemable prior to maturity,  shall not
be subject to any sinking fund and shall not be repurchasable at the option of a
Holder. The Debentures shall be issuable as Registered  Securities and shall not
be exchangeable for Bearer Securities.

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         8. Section 4.07 of the Indenture shall apply to the Debentures.

         9. Defeasance and covenant  defeasance under Article 8 of the Indenture
shall be applicable to the Debentures.

         10. The  Debentures  shall  initially be issued in whole in the form of
one or more global  Securities.  The Depository Trust Company, a clearing agency
registered under the Securities Exchange Act of 1934, as amended ("DTC"),  shall
initially serve as the depositary for such global Security or Securities. For so
long as DTC shall be the depositary,  all Debentures  shall be registered in its
name or in the name of a nominee thereof.  While the Debentures are evidenced by
one or more global  Securities,  the depositary or its nominee,  as the case may
be,  shall be the sole Holder  thereof  for all  purposes  under the  Indenture.
Neither  the  Company  nor the  Trustee  shall  have any  responsibility  or the
obligation to the  depositary's  participants or the beneficial  owners for whom
they act with respect to their  receipt from the  depositary  of payments on the
Debentures  or  notices  given  under the  Indenture.  The  global  Security  or
Securities  provided for  hereunder  shall bear such legend or legends as may be
required from time to time by the depositary.

         11. Except as hereinafter described, Debentures in definitive form will
not be issued.  Notwithstanding the foregoing,  in the event the Company decides
to discontinue the use of global Securities,  or if DTC is at any time unwilling
or unable to continue as depositary, and a successor depositary is not appointed
by the Company within 90 days, the Company will issue  individual  Debentures in
certificated form to owners of "book entry" ownership  interests in exchange for
the Debentures held by DTC or its nominee, as the case may be. In such instance,
an owner of a  "book-entry"  ownership  interest  will be  entitled  to physical
delivery  of  certificates  equal  in  principal  amount  to  such  "book-entry"
ownership  interest  and to  have  such  certificates  registered  in its  name.
Individual  certificates so issued will be issued in  denominations of $1,000 or
any multiple thereof.

         12.  Additional  terms regarding the Debentures are as set forth in the
form of Debenture set forth below.

                                       -3-





         13. The form of the Debentures shall be substantially as follows:

                 [Form of 5.70% Debenture due October 15, 2008]

No. R-___________                                                $_____________

                        WISCONSIN POWER AND LIGHT COMPANY
                      5.70% Debenture due October 15, 2008

                                CUSIP 976826 BB 2


WISCONSIN POWER AND LIGHT COMPANY
promises to pay to _____________________________________________________________

or registered assigns
the principal sum of _______________________________ Dollars on October 15, 2008

Interest Payment Dates:    April 15 and October 15
         Record Dates:     April 1 and October 1


                                            Dated:

FIRSTAR BANK MILWAUKEE, N.A.                WISCONSIN POWER AND LIGHT COMPANY
(As successor to Firstar Trust
  Company)
Transfer Agent and Paying Agent

                                            By:  _______________________________
                                                 [Title of Authorized Officer]
Authenticated:
FIRSTAR BANK MILWAUKEE, N.A.                                  (CORPORATE SEAL)
(As successor to Firstar Trust
  Company)
Registrar                                        _______________________________
                                                 [Assistant] Secretary

By:  ____________________________
     Authorized Signatory

                                       -4-





                        WISCONSIN POWER AND LIGHT COMPANY
                      5.70% Debenture due October 15, 2008

         Interest.   Wisconsin  Power  and  Light  Company  (the  "Company"),  a
Wisconsin corporation,  promises to pay interest on the principal amount of this
Security (as defined herein) at the rate per annum shown above. The Company will
pay  interest  semiannually  on April 15 and October 15 of each year  commencing
April 15, 1999. Interest on the Securities will accrue from the most recent date
to which  interest has been paid or, if no interest has been paid,  from October
30,  1998.  Interest  will be computed on the basis of a 360-day  year of twelve
30-day months.

         Method of Payment.  The Company will pay interest on the  Securities to
the persons who are registered holders of Securities at the close of business on
the record date for the next interest payment date, except as otherwise provided
in the Indenture. Holders must surrender Securities to a Paying Agent to collect
principal payments.  The Company will pay principal and interest in money of the
United  States that at the time of payment is legal tender for payment of public
and private  debts.  The Company may pay principal and interest by check payable
in such money. It may mail an interest check to a holder's registered address.

         Securities  Agents.   Initially,   Firstar  Bank  Milwaukee,  N.A.  (as
successor to Firstar Trust Company) will act as Paying Agent, Transfer Agent and
Registrar.  The Company may change any Paying  Agent or Transfer  Agent  without
notice.  The Company or any Affiliate may act in any such  capacity.  Subject to
certain conditions, the Company may change the Trustee.

         Indenture.   The  Company   issued  the   securities   of  this  series
(individually  a  "Security"  and  collectively  the   "Securities")   under  an
Indenture, dated as of June 20, 1997 (the "Indenture"),  between the Company and
Firstar Trust Company (subsequently  succeeded by Firstar Bank Milwaukee,  N.A.)
(the  "Trustee").  The  terms of the  Securities  include  those  stated  in the
Indenture and in the Officers' Certificate establishing the Securities and those
made part of the  Indenture  by the Trust  Indenture  Act of 1939 (15 U.S.  Code
Sections  77aaa-77bbbb).  Securityholders  are  referred to the  Indenture,  the
above-referenced  Officers'  Certificate  and such Act for a  statement  of such
terms.

         Maturity;  No  Redemption  Prior  to  Maturity.  The  principal  on the
Securities  shall be  payable  on  October  15,  2008.  The  Securities  are not
redeemable prior to maturity.

         Denominations,  Transfer,  Exchange.  The  Securities are in registered
form without coupons in  denominations  of $1,000 and whole multiples of $1,000.
The transfer of Securities  may be registered and Securities may be exchanged as
provided in the Indenture.  The Transfer Agent may require a holder, among other
things, to furnish  appropriate  endorsements and transfer  documents and to pay
any taxes and fees required by law or the Indenture.

         Persons  Deemed  Owners.  The  registered  holder of a Security  may be
treated as its owner for all purposes.


                                       -5-





         Amendments and Waivers. Subject to certain exceptions, the Indenture or
the Securities may be amended with the consent of the holders of not less than a
majority in aggregate  principal amount of the securities of all series affected
by the amendment.  Subject to certain  exceptions,  a default on a series may be
waived with the consent of the holders of a majority in principal  amount of the
series.

         Without  the  consent  of  any  Securityholder,  the  Indenture  or the
Securities may be amended, among other things, to cure any ambiguity,  omission,
defect or  inconsistency;  to provide for  assumption of Company  obligations to
Securityholders; or to make any change that does not materially adversely affect
the rights of any Securityholder.

         Restrictive Covenants. The Securities are unsecured general obligations
of the Company limited to $60,000,000  principal amount.  The Indenture does not
limit other unsecured debt. Section 4.07 of the Indenture,  which limits certain
mortgages  and other  liens,  will apply with  respect  to the  Securities.  The
limitations are subject to a number of important qualifications and exceptions.

         Successors. When a successor assumes all the obligations of the Company
under the Securities and the Indenture,  the Company will be released from those
obligations.

         Defeasance  Prior to  Maturity.  Subject  to  certain  conditions,  the
Company  at any time may  terminate  some or all of its  obligations  under  the
Securities  and the Indenture if the Company  deposits with the Trustee money or
U.S.  Government  Obligations  for the payment of principal  and interest on the
Securities to maturity. U.S. Government Obligations are securities backed by the
full  faith  and  credit  of  the  United  States  of  America  or  certificates
representing an ownership interest in such Obligations.

         Defaults and  Remedies.  An Event of Default  includes:  default for 60
days in payment of interest on the  Securities;  default in payment of principal
on the Securities; default by the Company for a specified period after notice to
it in  the  performance  of  any  of  its  other  agreements  applicable  to the
Securities;  and certain  events of  bankruptcy  or  insolvency.  If an Event of
Default occurs and is continuing,  the Trustee or the holders of at least 25% in
principal  amount  of the  Securities  may  declare  the  principal  of all  the
Securities to be due and payable immediately.

         Securityholders  may not enforce the Indenture or the Securities except
as provided in the Indenture.  The Trustee may require indemnity satisfactory to
it before it  enforces  the  Indenture  or the  Securities.  Subject  to certain
limitations,  holders of a majority in principal  amount of the  Securities  may
direct the  Trustee  in its  exercise  of any trust or power.  The  Trustee  may
withhold from Securityholders notice of any continuing default (except a default
in payment of principal or interest) if it determines that withholding notice is
in their interests. The Company must furnish an annual compliance certificate to
the Trustee.

         Trustee  Dealings with Company.  The Trustee,  in its individual or any
other capacity,  may make loans to, accept  deposits from, and perform  services
for the Company or its Affiliates, and may otherwise deal with those persons, as
if it were not Trustee.


                                       -6-





         No  Recourse   Against  Others.  A  director,   officer,   employee  or
shareholder,  as such,  of the  Company  shall  not have any  liability  for any
obligations  of the Company  under the  Securities  or the  Indenture or for any
claim  based  on,  in  respect  of or by  reason  of such  obligations  or their
creation.  Each  Securityholder  by accepting a Security waives and releases all
such  liability.  The waiver and release are part of the  consideration  for the
issue of the Securities.

         Authentication. This Security shall not be valid until authenticated by
a manual signature of the Registrar.

         Abbreviations.  Customary  abbreviations  may be used in the  name of a
Securityholder  or an assignee,  such as: TEN COM (=tenants in common),  TEN ENT
(=tenants by the entirety),  JT TEN (=joint  tenants with right of  survivorship
and not as tenants in common),  CUST  (=custodian),  U/G/M/A  (=Uniform Gifts to
Minors Act), and U/T/M/A (=Uniform Transfers to Minors Act).

         The Company will furnish to any Securityholder upon written request and
without  charge a copy of the  Indenture and the  Officers'  Certificate,  which
contains  the  text  of  this  Security.  Requests  may be  made  to:  Corporate
Secretary,  Wisconsin  Power  and Light  Company,  222 West  Washington  Avenue,
Madison, Wisconsin 53703.

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

                            [Form of Assignment Form]

                                 ASSIGNMENT FORM

         To assign this Security, fill in the form below:

         I or we  assign  and  transfer  this  Security  to ____________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
(Print or type assignee's name, address and zip code)




                                       -7-




(Insert assignee's soc. sec. or tax I.D. no.)

and  irrevocably  appoint  __________________________________________  agent  to
transfer  this  Security on the books of the Company.  The agent may  substitute
another to act for him.


Date:    ____________, ____       Your signature:  _____________________________

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


        (Sign exactly as your name appears on the face of this Security)


Signature Guaranteed:



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

                                      * * *

         IN WITNESS WHEREOF, we have set our hands and the corporate seal of the
Company as of the day and year first above written.

                                       WISCONSIN POWER AND LIGHT COMPANY



                                       By:      ________________________________
                                                Edward M. Gleason
                                                Vice President-Treasurer and
                                                  Corporate Secretary



                                       By:      ________________________________
                                                Robert A. Rusch
                                                Assistant Treasurer


                                       -8-