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                                                                     EXHIBIT 4

                               [Form of Indenture]

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                              WISCONSIN GAS COMPANY


                                       and


                         U.S. BANK NATIONAL ASSOCIATION,


                                   as Trustee


                                   ----------


                                    INDENTURE


                       Dated as of ________________, 2003


                                   ----------


                                 DEBT SECURITIES


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                              WISCONSIN GAS COMPANY

                          PARTIAL CROSS-REFERENCE TABLE

                           Trust Indenture Act of 1939
                and Indenture dated as of ________________, 2003

Indenture Section                                      TIA Section

 2.05..................................................317(b)
 2.06..................................................312(a), 313(c)
 2.11..................................................316(a)(last sentence)
 4.04..................................................314(a)(4)
 4.05..................................................314(a)(1)
 6.03..................................................317(a)(1)
 6.04..................................................316(a)(1)(B)
 6.05..................................................316(a)(1)(A)\
 6.07..................................................317(a)(1)
 7.01..................................................315(a), 315(d)
 7.04..................................................315(b)
 7.05..................................................313(a), 313(d)
 7.07..................................................310(a), 310(b)
 7.09..................................................310(a)(2)
 8.02..................................................310(a),310(b)
 9.04..................................................316(c)
10.01............................... ..................318(a)
10.02..................................................313(c)
10.03..................................................314(c)(1), 314(c)(2)
10.04..................................................314(e)

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                              WISCONSIN GAS COMPANY
                            DEBT SECURITIES INDENTURE
                       Dated As Of ________________, 2003

                                TABLE OF CONTENTS
                                                                          Page
                                                                          ----

ARTICLE 1 -     DEFINITIONS..................................................1

    Section 1.01   Definitions...............................................1

    Section 1.02   Other Definitions.........................................3

    Section 1.03   Rules of Construction.....................................3

ARTICLE 2 -     THE SECURITIES...............................................3

    Section 2.01   Issuable in Series........................................3

    Section 2.02   Execution and Authentication..............................5

    Section 2.03   Securities Agents.........................................6

    Section 2.04   Bearer Securities.........................................6

    Section 2.05   Paying Agent to Hold Money in Trust.......................7

    Section 2.06   Securityholder Lists......................................7

    Section 2.07   Transfer and Exchange.....................................7

    Section 2.08   Replacement Securities....................................8

    Section 2.09   Outstanding Securities....................................8

    Section 2.10   Discounted Securities.....................................8

    Section 2.11   Treasury Securities.......................................9

    Section 2.12   Global Securities.........................................9

    Section 2.13   Temporary Securities......................................9

    Section 2.14   Cancellation..............................................9

    Section 2.15   Defaulted Interest.......................................10

ARTICLE 3 -     REDEMPTION..................................................10

    Section 3.01   Notices to Trustee.......................................10

    Section 3.02   Selection of Securities to Be Redeemed...................10

    Section 3.03   Notice of Redemption.....................................11

    Section 3.04   Effect of Notice of Redemption...........................11

    Section 3.05   Payment of Redemption Price..............................12

    Section 3.06   Securities Redeemed in Part..............................12

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ARTICLE 4 -     COVENANTS...................................................12

    Section 4.01   Payment of Securities....................................12

    Section 4.02   Overdue Interest.........................................13

    Section 4.03   No Lien Created, etc.....................................13

    Section 4.04   Compliance Certificate...................................13

    Section 4.05   SEC Reports..............................................13

    Section 4.06   Certain Definitions......................................13

    Section 4.07   Limitations on Liens.....................................16

ARTICLE 5 -     SUCCESSORS..................................................16

    Section 5.01   When Company May Merge, etc..............................16

ARTICLE 6 -     DEFAULTS AND REMEDIES.......................................17

    Section 6.01   Events of Default........................................17

    Section 6.02   Acceleration.............................................18

    Section 6.03   Other Remedies...........................................18

    Section 6.04   Waiver of Past Defaults..................................19

    Section 6.05   Control by Majority......................................19

    Section 6.06   Limitation on Suits......................................19

    Section 6.07   Collection Suit by Trustee...............................19

    Section 6.08   Priorities...............................................20

ARTICLE 7 -     TRUSTEE.....................................................20

    Section 7.01   Rights of Trustee........................................20

    Section 7.02   Individual Rights of Trustee.............................21

    Section 7.03   Trustee's Disclaimer.....................................21

    Section 7.04   Notice of Defaults.......................................21

    Section 7.05   Reports by Trustee to Holders............................21

    Section 7.06   Compensation and Indemnity...............................21

    Section 7.07   Replacement of Trustee...................................22

    Section 7.08   Successor Trustee by Merger, etc.........................23

    Section 7.09   Trustee's Capital and Surplus............................23

ARTICLE 8 -     DISCHARGE OF INDENTURE......................................23

    Section 8.01   Defeasance...............................................23

    Section 8.02   Conditions to Defeasance.................................24

    Section 8.03   Application of Trust Money...............................25

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    Section 8.04   Repayment to Company.....................................25

ARTICLE 9 -     AMENDMENTS AND WAIVERS......................................25

    Section 9.01   Without Consent of Holders...............................25

    Section 9.02   With Consent of Holders..................................26

    Section 9.03   Compliance with Trust Indenture Act......................26

    Section 9.04   Effect of Consents.......................................26

    Section 9.05   Notation on or Exchange of Securities....................27

    Section 9.06   Trustee Protected........................................27

ARTICLE 10 -    MISCELLANEOUS...............................................27

    Section 10.01  Trust Indenture Act......................................27

    Section 10.02  Notices..................................................27

    Section 10.03  Certificate and Opinion as to Conditions Precedent.......28

    Section 10.04  Statements Required in Certificate or Opinion............29

    Section 10.05  Rules by Company and Agents..............................29

    Section 10.06  Legal Holidays...........................................29

    Section 10.07  No Recourse Against Others...............................29

    Section 10.08  Duplicate Originals......................................29

    Section 10.09  Governing Law............................................29

SIGNATURES    ..............................................................30

EXHIBIT A     .............................................................A-1

EXHIBIT B     .............................................................B-1

NOTES TO EXHIBITS A AND B

EXHIBIT C     .............................................................C-1


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     INDENTURE dated as of ________________, 2003 between WISCONSIN GAS COMPANY,
a Wisconsin corporation (the "Company"), and U.S. BANK NATIONAL ASSOCIATION, a
national banking association (the "Trustee").

     Each party agrees as follows for the benefit of the Holders of the
Company's debt securities issued under this Indenture:

                             ARTICLE 1 - DEFINITIONS

SECTION 1.01  Definitions.

     "Affiliate" means any person directly or indirectly controlling or
controlled by or under direct or indirect common control with the Company.

     "Agent" means any Registrar, Transfer Agent or Paying Agent.

     "Authorized Newspaper" means a newspaper that is:

     (1)  printed in the English language or in an official language of the
          country of publication;

     (2)  customarily published on each business day in the place of
          publication; and

     (3)  of general circulation in the relevant place or in the financial
          community of such place.

Whenever successive  publications in an Authorized Newspaper are required,  they
may be made on the same or different  business days and in the same or different
Authorized Newspapers.

     "Bearer Security" means a Security payable to bearer.

     "Board" means the Board of Directors of the Company or any authorized
committee of the Board.

     "Company" means the party named as such above until a successor replaces it
and thereafter means the successor.

     "Coupon" means an interest coupon for a Bearer Security.

     "Default" means any event which is, or after notice or passage of time
would be, an Event of Default.

     "Discounted Security" means a Security where the amount of principal due
upon acceleration is less than the stated principal amount.

     "Holder" or "Securityholder" means the person in whose name a Registered
Security is registered and the bearer of a Bearer Security or coupon.

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     "Indenture" means this Indenture and any Securities Resolution as amended
from time to time.

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

     "Officer" means the Chairman of the Board, any Vice Chairman, the
President, any Executive Vice President, any Senior Vice President, any Vice
President, the Treasurer, the Secretary, the Controller, any Assistant
Treasurer, any Assistant Secretary or any Assistant Controller of the Company.

     "Officers' Certificate" means a certificate signed by any one or more
Officers.

     "Opinion of Counsel" means a written opinion, complying with Sections 10.03
and 10.04 hereof, from legal counsel who is acceptable to the Trustee. The
counsel may be an employee of or counsel to the Company or the Trustee.

     "Principal" of a debt security means the principal of the security plus the
premium, if and when applicable, on the security.

     "Registered Security" means a Security registered as to principal and
interest by the Registrar.

     "SEC" means the Securities and Exchange Commission.

     "Securities" means the debt securities issued under this Indenture.

     "Securities Resolution" means a resolution establishing a series of
Securities adopted by the Board or by an Officer or committee of Officers
pursuant to Board delegation or a supplemental indenture establishing such
series of Securities executed by an authorized Officer.

     "Series" means a series of Securities or the Securities of the series.

     "Subsidiary" means a corporation or other entity a majority of whose Voting
Stock (or comparable securities) is owned by the Company or a Subsidiary.

     "TIA" means the Trust Indenture Act of 1939 (15 U.S. Code Sections
77aaa-77bbbb), as amended by the Trust Indenture Reform Act of 1990, as in
effect on the date shown above.

     "Trustee" means the party named as such above until a successor replaces it
and thereafter means the successor.

     "Trust Officer" means the Chairman of the Board, the President or any other
officer or assistant officer of the Trustee assigned by the Trustee to
administer its corporate trust matters.

     "United States" means the United States of America, its territories and
possessions and other areas subject to its jurisdiction.

     "Voting Stock" means capital stock having voting power under ordinary
circumstances to elect directors.

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     "Yield to Maturity" means the yield to maturity on a Security at the time
of its issuance or at the most recent determination of interest on the Security.

SECTION 1.02  Other Definitions.

     Term                                                  Defined in Section

     "Bankruptcy Law"..............................................6.01
     "Conditional Redemption"......................................3.04
     "covenant defeasance option"..................................8.01
     "Custodian"...................................................6.01
     "Event of Default"............................................6.01
     "legal defeasance option".....................................8.01
     "Legal Holiday"..............................................10.06
     "Paying Agent"................................................2.03
     "Permitted Encumbrances"......................................4.06
     "Person"......................................................4.06
     "Registrar"...................................................2.03
     "Total Assets"................................................4.06
     "Transfer Agent"..............................................2.03
     "Treasury Regulations"........................................2.04
     "U.S. Government Obligations".................................8.02

SECTION 1.03  Rules of Construction.

Unless the context otherwise requires:

     (1)  a term has the meaning assigned to it;

     (2)  an accounting term not otherwise defined has the meaning assigned to
          it in accordance with generally accepted accounting principles in the
          United States;

     (3)  generally accepted accounting principles are those applicable from
          time to time;

     (4)  all terms used in this Indenture that are defined by the TIA, defined
          by TIA reference to another statute or defined by SEC rule under the
          TIA have the meanings assigned to them by such definitions;

     (5)  "or" is not exclusive; and

     (6)  words in the singular include the plural, and in the plural include
          the singular.

                           ARTICLE 2 - THE SECURITIES

SECTION 2.01  Issuable in Series.

     The aggregate principal amount of Securities that may be issued under this
Indenture is unlimited. The Securities may be issued from time to time in one or
more series. Each series

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shall be created by a Securities Resolution that establishes the terms of the
series, which may include the following:

     (1)  the title of the series;

     (2)  the aggregate principal amount of the series;

     (3)  the interest rate, if any, or method of calculating the interest rate;

     (4)  the date from which interest will accrue;

     (5)  the record dates for interest payable on Registered Securities;

     (6)  the dates when principal and interest are payable;

     (7)  the manner of paying principal and interest;

     (8)  the places where principal and interest are payable;

     (9)  the Registrar, Transfer Agent and Paying Agent;

     (10) the terms of any mandatory or optional redemption by the Company,
          including any sinking fund;

     (11) the terms of any redemption at the option of Holders;

     (12) the denominations in which Securities are issuable;

     (13) whether Securities will be issuable as Registered Securities or Bearer
          Securities;

     (14) whether and upon what terms Registered Securities and Bearer
          Securities may be exchanged;

     (15) whether any Securities will be represented by a Security in global
          form and the terms of any global Security;

     (16) the terms of any tax indemnity;

     (17) the currencies (including any composite currency) in which principal
          or interest may be paid and if payments of principal or interest may
          be made in a currency other than that in which Securities are
          denominated, the manner for determining such payments;

     (18) if amounts of principal or interest may be determined by reference to
          an index, formula or other method, the manner for determining such
          amounts;

     (19) provisions for electronic issuance of Securities or for Securities in
          uncertificated form;

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     (20) the portion of principal payable upon acceleration of a Discounted
          Security;

     (21) whether Section 4.07 applies, and any Events of Default or covenants
          in addition to or in lieu of those set forth in this Indenture;

     (22) whether and upon what terms Securities may be defeased;

     (23) the forms of the Securities or any coupon, which may be in the form of
          Exhibit A or B;

     (24) any terms that may be required by or advisable under U.S. or other
          applicable laws;

     (25) the ranking of the Securities, including the relative degree, if any,
          to which the Securities of such series shall be subordinated to one or
          more other series of Securities in right of payment, whether
          outstanding or not;

     (26) any provisions relating to extending or shortening the date on which
          the principal and premium, if any, of the Securities of such series is
          payable;

     (27) any provisions relating to the deferral of payment of any interest;
          and

     (28) any other terms not inconsistent with this Indenture.

     All Securities of one series need not be issued at the same time and,
unless otherwise provided, a series may be reopened for issuances of additional
Securities of such series.

     The creation and issuance of a series and the authentication and delivery
thereof are not subject to any conditions precedent.

SECTION 2.02  Execution and Authentication.

     Two Officers shall sign the Securities by manual or facsimile signature.
The Company's seal shall be reproduced on the Securities, which seal may be
affixed or in facsimile form. An Officer shall sign any coupons by facsimile
signature.

     If an Officer whose signature is on a Security or its coupons no longer
holds that office at the time the Security is authenticated or delivered, the
Security and coupons shall nevertheless be valid.

     A Security and its coupons shall not be valid until the Security is
authenticated by the manual signature of the Registrar. The signature shall be
conclusive evidence that the Security has been authenticated under this
Indenture.

     Each Registered Security shall be dated the date of its authentication.
Each Bearer Security shall be dated the date of its authentication or as
provided in the Securities Resolution.

     Securities may have notations, legends or endorsements required by law,
stock exchange rule, agreement or usage, which shall be provided to the Trustee
in writing by the Company.

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     In the event Securities are issued in electronic or other uncertificated
form, such Securities may be validly issued without the signatures or seal
contemplated by this Section 2.02.

SECTION 2.03  Securities Agents.

     The Company shall maintain an office or agency where Securities may be
authenticated ("Registrar"), where Securities may be presented for registration
of transfer or for exchange ("Transfer Agent") and where Securities may be
presented for payment ("Paying Agent"). Whenever the Company must issue or
deliver Securities pursuant to this Indenture, the Registrar shall authenticate
the Securities at the Company's request. The Transfer Agent shall keep a
register of the Securities and of their transfer and exchange.

     The Trustee shall be, and is hereby appointed as, the Registrar. The
Company may appoint more than one Transfer Agent or Paying Agent for a series.
The Company shall notify the Trustee of the name and address of any Agent not a
party to this Indenture. If the Company fails to maintain a Transfer Agent or
Paying Agent for a series, the Trustee shall act as such.

SECTION 2.04  Bearer Securities.

     U.S. laws and Treasury Regulations restrict sales or exchanges of and
payments on Bearer Securities. Therefore, except as provided below:

     (1)  Bearer Securities will be offered, sold and delivered only outside the
          United States and will be delivered only upon presentation of a
          certificate in a form prescribed by the Company to comply with U.S.
          laws and regulations.

     (2)  Bearer Securities will not be issued in exchange for Registered
          Securities.

     (3)  All payments of principal and interest (including original issue
          discount) on Bearer Securities will be made outside the United States
          by a Paying Agent located outside the United States unless the Company
          determines that:

          (A)  such payments may not be made by such Paying Agent because the
               payments are illegal or prevented by exchange controls as
               described in Treasury Regulation section 1.163-5(c)(2)(v); and

          (B)  making the payments in the United States would not have an
               adverse tax effect on the Company.

     If there is a change in the relevant provisions of U.S. laws or Treasury
Regulations or the judicial or administrative interpretation thereof, a
restriction set forth in paragraph (1), (2) or (3) above will not apply to a
series if the Company determines that the relevant provisions no longer apply to
the series or that failure to comply with the relevant provisions would not have
an adverse tax effect on the Company or on Securityholders or cause the series
to be treated as "registration-required" obligations under U.S. law.

     The Company shall notify the Trustee in writing of any determinations by
the Company under this Section.

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     "Treasury Regulations" means regulations of the U.S. Treasury Department
under the Internal Revenue Code of 1986, as amended.

SECTION 2.05  Paying Agent to Hold Money in Trust.

     The Company shall require each Paying Agent for a series other than the
Trustee to agree in writing that the Paying Agent will hold in trust for the
benefit of the persons entitled thereto all money held by the Paying Agent for
the payment of principal of or interest on the series, and will notify the
Trustee in writing of any default by the Company in making any such payment.

     While any such default continues, the Trustee may require a Paying Agent to
pay all money so held by it to the Trustee. The Company at any time may require
a Paying Agent to pay all money held by it to the Trustee. Upon payment over to
the Trustee, the Paying Agent shall have no further liability for the money.

     If the Company or an Affiliate acts as Paying Agent for a series, it shall
segregate and hold as a separate trust fund all money held by it as Paying Agent
for the series.

SECTION 2.06  Securityholder Lists.

     The Trustee shall preserve in as current a form as is reasonably
practicable the most recent list available to it of the names and addresses of
Securityholders. If the Trustee is not the Transfer Agent, the Company shall
furnish to the Trustee semiannually and at such other times as the Trustee may
request a list in such form and as of such date as the Trustee may reasonably
require of the names and addresses of Holders of Registered Securities and
Holders of Bearer Securities whose names are on the list referred to below.

     The Transfer Agent shall keep a list of the names and addresses of Holders
of Bearer Securities who file a request to be included on such list. A request
will remain in effect for two years but successive requests may be made.

     Whenever the Company or the Trustee is required to mail a notice to all
Holders of Registered Securities of a series, it also shall mail the notice to
Holders of Bearer Securities of the series whose names are on the list, if any.

     Whenever the Company is required to publish a notice to all Holders of
Bearer Securities of a series, it also shall mail the notice to such of them
whose names are on the list, if any.

SECTION 2.07  Transfer and Exchange.

     Where Registered Securities of a series are presented to the Transfer Agent
with a request to register a transfer or to exchange them for an equal principal
amount of Registered Securities of other denominations of the series, the
Transfer Agent shall register the transfer or make the exchange if its
requirements for such transactions are met. Where Bearer Securities of a series
are presented to the Transfer Agent with a request to exchange them for an equal
principal amount of Bearer Securities of other denominations of the series, the
Transfer Agent shall make the exchange if its requirements for such transactions
are met.

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     The Transfer Agent may require a Holder to pay a sum sufficient to cover
any taxes imposed on a transfer or exchange.

     If a series provides for Registered and Bearer Securities and for their
exchange, Bearer Securities may be exchanged for Registered Securities and
Registered Securities may be exchanged for Bearer Securities as provided in the
Securities or the Securities Resolution establishing the series if the
requirements of the Transfer Agent for such transactions are met and if Section
2.04 permits the exchange.

SECTION 2.08  Replacement Securities.

     If the Holder of a Security or coupon claims that it has been lost,
destroyed or wrongfully taken, then, in the absence of notice to the Company or
the Trustee that the Security or coupon has been acquired by a bona fide
purchaser, the Company shall issue a replacement Security or coupon if the
Company and the Trustee receive:

     (1)  evidence satisfactory to them of the loss, destruction or taking;

     (2)  an indemnity bond satisfactory to them; and

     (3)  payment of a sum sufficient to cover their expenses and any taxes for
          replacing the Security or coupon.

     A replacement Security shall have coupons attached corresponding to those,
if any, on the replaced Security.

     Every replacement Security or coupon is an additional obligation of the
Company.

SECTION 2.09  Outstanding Securities.

     The Securities outstanding at any time are all the Securities authenticated
by the Registrar except for those canceled by it, those delivered to it for
cancellation, and those described in this Section as not outstanding.

     If a Security is replaced pursuant to Section 2.08, it ceases to be
outstanding unless the Trustee and the Company receive proof satisfactory to
them that the replaced Security is held by a bona fide purchaser.

     If Securities are considered paid under Section 4.01, they cease to be
outstanding and interest on them ceases to accrue.

     A Security does not cease to be outstanding because the Company or an
Affiliate holds the Security.

SECTION 2.10  Discounted Securities.

     In determining whether the Holders of the required principal amount of
Securities have concurred in any direction, waiver or consent, the principal
amount of a Discounted Security

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shall be the amount of principal that would be due as of the date of such
determination if payment of the Security were accelerated on that date.

SECTION 2.11  Treasury Securities.

     In determining whether the Holders of the required principal amount of
Securities have concurred in any direction, waiver or consent, Securities owned
by the Company or an Affiliate shall be disregarded, except that for the
purposes of determining whether the Trustee shall be protected in relying on any
such direction, waiver or consent, only Securities for which the Trustee has
received an Officers' Certificate stating that such Securities are so owned
shall be so disregarded.

SECTION 2.12  Global Securities.

     If the Securities Resolution establishing a series so provides, the Company
may issue some or all of the Securities of the series in temporary or permanent
global form. A global Security may be in registered form, in bearer form with or
without coupons or in uncertificated form. A global Security shall represent
that amount of Securities of a series as specified in the global Security or as
endorsed thereon from time to time. At the Company's request, the Registrar
shall endorse a global Security to reflect the amount of any increase or
decrease in the Securities represented thereby.

     The Company may issue a global Security only to a depositary designated by
the Company. A depositary may transfer a global Security only as a whole to its
nominee or to a successor depositary.

     The Securities Resolution may establish, among other things, the manner of
paying principal and interest on a global Security and whether and upon what
terms a beneficial owner of an interest in a global Security may exchange such
interest for definitive Securities.

     The Company, an Affiliate, the Trustee and any Agent shall not be
responsible for any acts or omissions of a depositary, for any depositary
records of beneficial ownership interests or for any transactions between the
depositary and beneficial owners.

SECTION 2.13  Temporary Securities.

     Until definitive Securities of a series are ready for delivery, the Company
may use temporary Securities. Temporary Securities shall be substantially in the
form of definitive Securities but may have variations that the Company considers
appropriate for temporary Securities. Temporary Securities may be in global
form. Temporary Bearer Securities may have one or more coupons or no coupons.
Without unreasonable delay, the Company shall deliver definitive Securities in
exchange for temporary Securities.

SECTION 2.14  Cancellation.

     The Company at any time may deliver Securities to the Registrar for
cancellation. The Transfer Agent and the Paying Agent shall forward to the
Registrar any Securities and coupons surrendered to them for payment, exchange
or registration of transfer. The Registrar shall cancel

                                       9

<PAGE>

all Securities or coupons surrendered for payment, registration of transfer,
exchange or cancellation as follows: the Registrar will cancel all Registered
Securities and matured coupons. The Registrar also will cancel all Bearer
Securities and unmatured coupons unless the Company requests the Registrar to
hold the same for redelivery. Any Bearer Securities so held shall be considered
delivered for cancellation under Section 2.09. The Registrar shall destroy
canceled Securities and coupons and deliver a certificate of cancellation
thereof to the Company unless the Company otherwise directs.

     Unless the Securities Resolution establishing a series otherwise provides,
the Company may not issue new Securities to replace Securities that the Company
has paid or that the Company has delivered to the Registrar for cancellation.

SECTION 2.15  Defaulted Interest.

     If the Company defaults in a payment of interest on Registered Securities,
it need not pay the defaulted interest to Holders on the regular record date.
The Company may fix a special record date for determining Holders entitled to
receive defaulted interest or the Company may pay defaulted interest in any
other lawful manner.

                             ARTICLE 3 - REDEMPTION

SECTION 3.01  Notices to Trustee.

     Securities of a series that are redeemable before maturity shall be
redeemable in accordance with their terms and, unless the Securities Resolution
establishing the series otherwise provides, in accordance with this Article.

     In the case of a redemption by the Company, the Company shall notify the
Trustee of the redemption date and the principal amount of Securities to be
redeemed. The Company shall notify the Trustee at least 35 days before the
redemption date unless a shorter notice is satisfactory to the Trustee.

     If the Company is required to redeem Securities, it may reduce the
principal amount of Securities required to be redeemed to the extent it is
permitted a credit by the terms of the Securities and it notifies the Trustee of
the amount of the credit and the basis for it. If the reduction is based on a
credit for acquired or redeemed Securities that the Company has not previously
delivered to the Registrar for cancellation, the Company shall deliver the
Securities at the same time as the notice.

SECTION 3.02  Selection of Securities to Be Redeemed.

     If less than all the Securities of a series are to be redeemed, the Trustee
shall select the Securities to be redeemed pro rata or by any other method the
Trustee considers fair and appropriate, unless the Company otherwise directs in
writing. The Trustee shall make the selection from Securities of the series
outstanding not previously called for redemption. The Trustee may select for
redemption portions of the principal of Securities having denominations

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larger than the minimum denomination for the series. Securities and portions
thereof selected for redemption shall be in amounts equal to the minimum
denomination for the series or an integral multiple thereof. Provisions of this
Indenture that apply to Securities called for redemption also apply to portions
of Securities called for redemption.

SECTION 3.03  Notice of Redemption.

     At least 30 days but not more than 60 days before a redemption date, or
within such other period as may be specified in the Securities Resolution
creating the series of Securities to be redeemed, the Company shall mail a
notice of redemption by first-class mail to each Holder of Registered Securities
whose Securities are to be redeemed.

     If Bearer Securities are to be redeemed, the Company shall publish a notice
of redemption in an Authorized Newspaper as provided in the Securities.

     A notice shall identify the Securities of the series to be redeemed and
shall state:

     (1)  the redemption date;

     (2)  the redemption price;

     (3)  the name and address of the Paying Agent;

     (4)  that Securities called for redemption, together with all coupons, if
          any, maturing after the redemption date, must be surrendered to the
          Paying Agent to collect the redemption price;

     (5)  that interest on Securities called for redemption ceases to accrue on
          and after the redemption date;

     (6)  whether the redemption by the Company is mandatory or optional; and

     (7)  whether the redemption is conditional as provided in Section 3.04, the
          terms of the condition, and that, if the condition is not satisfied or
          is not waived by the Company, the Securities will not be redeemed and
          such a failure to redeem will not constitute an Event of Default.

     A redemption notice given by publication need not identify Registered
Securities to be redeemed.

     At the Company's request, the Trustee shall give the notice of redemption
in the Company's name and at its expense.

SECTION 3.04  Effect of Notice of Redemption.

     Except as provided below, once notice of redemption is given, Securities
called for redemption become due and payable on the redemption date at the
redemption price stated in the notice.

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     A notice of redemption may provide that it is subject to the occurrence of
any event before the date fixed for such redemption as described in such notice
("Conditional Redemption") and such notice of Conditional Redemption shall be of
no effect unless all such conditions to the redemption have occurred on or
before such date or have been waived by the Company.

SECTION 3.05  Payment of Redemption Price.

     On or before the redemption date, the Company shall deposit with the Paying
Agent money sufficient to pay the redemption price of and accrued interest on
all Securities to be redeemed on that date.

     When the Holder of a Security surrenders it for redemption in accordance
with the redemption notice, the Company shall pay to the Holder on the
redemption date the redemption price and accrued interest to such date, except
that:

     (1)  the Company will pay any such interest (except defaulted interest) to
          Holders on the record date of Registered Securities if the redemption
          date occurs on an interest payment date; and

     (2)  the Company will pay any such interest to Holders of coupons that
          mature on or before the redemption date upon surrender of such coupons
          to the Paying Agent.

     Coupons maturing after the redemption date on a called Security are void
absent a payment default on that date. Nevertheless, if a Holder surrenders for
redemption a Bearer Security missing any such coupons, the Company may deduct
the face amount of such coupons from the redemption price. If thereafter the
Holder surrenders to the Paying Agent the missing coupons, the Company will
return the amount so deducted. The Company also may waive surrender of the
missing coupons if it receives an indemnity bond satisfactory to the Company.

SECTION 3.06  Securities Redeemed in Part.

     Upon surrender of a Security that is redeemed in part, the Company shall
deliver to the Holder a new Security of the same series equal in principal
amount to the unredeemed portion of the Security surrendered.

                              ARTICLE 4 - COVENANTS

SECTION 4.01  Payment of Securities.

     The Company shall pay the principal of and interest on a series in
accordance with the terms of the Securities for the series, any related coupons,
and this Indenture. On each payment date, the Company shall have deposited with
the Paying Agent in funds which are then immediately available money sufficient
to pay all principal and interest then due on the series. Principal and interest
on a series shall be considered paid on the date due if the Paying Agent for

                                       12

<PAGE>

the series holds on that date money sufficient to pay all principal and interest
then due on the series.

SECTION 4.02  Overdue Interest.

     Unless the Securities Resolution establishing a series otherwise provides,
the Company shall pay interest on overdue principal of a Security of a series at
the rate (or Yield to Maturity in the case of a Discounted Security) borne by
the series; it shall pay interest on overdue installments of interest at the
same rate or Yield to Maturity to the extent lawful.

SECTION 4.03  No Lien Created, etc.

     This Indenture and the Securities do not create a Lien, charge or
encumbrance on any property of the Company or any Subsidiary.

SECTION 4.04  Compliance Certificate.

     The Company shall deliver to the Trustee, within 120 days after the end of
each fiscal year of the Company, a brief certificate signed by the principal
executive officer, principal financial officer or principal accounting officer
of the Company, as to the signer's knowledge of the Company's compliance with
all conditions and covenants under this Indenture (determined without regard to
any period of grace or requirement of notice provided herein).

     Any other obligor on the Securities also shall deliver to the Trustee such
a certificate similarly signed as to its compliance with this Indenture within
120 days after the end of each of its fiscal years.

     The certificates need not comply with Section 10.04.

SECTION 4.05  SEC Reports.

     The Company shall provide to the Trustee, within 15 days after the Company
is required to file the same with the SEC, copies of the annual reports and of
the information, documents, and other reports (or such portions of the foregoing
as the SEC may prescribe) which the Company is required to file with the SEC
pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934.

     Any other obligor on the Securities shall do likewise as to the above items
which it is required to file with the SEC pursuant to those Sections.

SECTION 4.06  Certain Definitions.

     "Permitted Encumbrances" means any of the following:

     (1)  Liens of taxes, assessments or governmental charges for the then
          current year and taxes, assessments or governmental charges not then
          delinquent; Liens for workers' compensation awards and similar
          obligations not then delinquent; mechanics', laborers', materialmen's
          and similar Liens not then delinquent; and

                                       13

<PAGE>

          any of such Liens, whether or not delinquent, whose validity is at the
          time being contested in good faith by the Company or any Subsidiary;

     (2)  Liens and charges incidental to construction or current operations
          which have not at the time been filed or asserted or the payment of
          which has been adequately secured or which, in the opinion of counsel,
          are not material in amount;

     (3)  Liens, securing obligations neither assumed by the Company or any
          Subsidiary nor on account of which any of them customarily pays
          interest directly or indirectly, existing, either at the date hereof,
          or, as to property hereafter acquired, at the time of acquisition by
          the Company or a Subsidiary;

     (4)  Any right which any municipal or governmental body or agency may have
          by virtue of any franchise, license, contract or statute to purchase,
          or designate a purchaser of or order the sale of, any property of the
          Company or any Subsidiary upon payment of reasonable compensation
          therefor, or to terminate any franchise, license or other rights or to
          regulate the property and business of the Company or any Subsidiary;

     (5)  The Lien of judgments covered by insurance, or upon appeal and
          covered, if necessary, by the filing of an appeal bond, or if not so
          covered not exceeding at any one time $10,000,000 in aggregate amount;

     (6)  Easements or reservations in respect of any property of the Company or
          any Subsidiary for the purpose of roads, pipelines, utility
          transmission and distribution lines or other rights-of-way and similar
          purposes, zoning ordinances, regulations, reservations, restrictions,
          covenants, party wall agreements, conditions of record and other
          encumbrances (other than to secure the payment of money), none of
          which, in the opinion of counsel, are such as to interfere with the
          proper operation and development of the property affected thereby in
          the business of the Company and its Subsidiaries for the use intended;

     (7)  Any Lien or encumbrance, moneys sufficient for the discharge of which
          have been deposited in trust with the Trustee hereunder or with the
          trustee or mortgagee under the instrument evidencing such Lien or
          encumbrance, with irrevocable authority to the Trustee hereunder or to
          such other trustee or mortgagee to apply such moneys to the discharge
          of such Lien or encumbrance to the extent required for such purpose;

     (8)  Any defects of title and any terms, conditions, agreements, covenants,
          exceptions and reservations expressed or provided in deeds or other
          instruments, respectively, under and by virtue of which the Company or
          any Subsidiary has acquired any property or shall hereafter acquire
          any property, none of which, in the opinion of counsel, materially
          adversely affects the operation of the properties of the Company and
          its Subsidiaries, taken as a whole;

     (9)  The pledge of cash or marketable securities for the purpose of
          obtaining any indemnity, performance or other similar bonds in the
          ordinary course of business,

                                       14

<PAGE>

          or as security for the payment of taxes or other assessments being
          contested in good faith, or for the purpose of obtaining a stay or
          discharge in the course of any legal proceedings;

     (10) The pledge or assignment in the ordinary course of business of
          electricity, gas (either natural or artificial), steam, water or other
          utility accounts receivable or customers' installment paper;

     (11) Rights reserved to or vested in others to take or receive any part of
          the electricity, gas (either natural or artificial), steam, water or
          other utility products or any by-products thereof generated or
          produced by or from any properties of the Company or with respect to
          any other rights concerning electricity, gas (either natural or
          artificial), steam, water or other utility product supply,
          transportation, or storage which are in use in the ordinary course of
          the electricity, gas (either natural or artificial), steam, water or
          other utility business;

     (12) Any landlord's Lien;

     (13) Liens created or assumed by the Company or a Subsidiary in connection
          with the issuance of debt securities, the interest on which is
          excludable from the gross income of the holders of such securities
          pursuant to Section 103 of the Internal Revenue Code of 1986, or any
          successor section, for purposes of financing, in whole or in part, the
          acquisition or construction of property to be used by the Company or a
          Subsidiary, but such Liens shall be limited to the property so
          financed (and the real estate on which such property is to be
          located);

     (14) Liens incurred pursuant to Section 7.06;

     (15) Liens affixing to property of the Company or a Subsidiary at the time
          a Person consolidates with or merges into, or transfers all or
          substantially all of its property to, the Company or a Subsidiary,
          provided that in the opinion of the Board or Company management
          (evidenced by a certified Board resolution or an Officers' Certificate
          delivered to the Trustee) the property acquired pursuant to the
          consolidation, merger or asset transfer is adequate security for the
          Lien; and

     (16) Liens or encumbrances not otherwise permitted if, at the time of
          incurrence and after giving effect thereto, the aggregate of all
          obligations of the Company and its Subsidiaries secured thereby does
          not exceed 15% of Total Assets.

     "Person" means any individual, partnership, joint venture, firm,
corporation, association, trust, limited liability company or other enterprise
(whether or not incorporated), or any government or political subdivision or any
agency, department or instrumentality thereof.

     "Total Assets" means all assets of the Company as shown on its most recent
quarterly or annual consolidated balance sheet, as determined in accordance with
generally accepted accounting principles in the United States applied on a
consistent basis.

                                       15

<PAGE>
SECTION 4.07  Limitations on Liens.

     So long as there remain outstanding any Securities of any series to which
this Section 4.07 applies under the terms of the series, the Company will not,
and will not permit any Subsidiary to, create or suffer to be created or to
exist any Lien on any of its properties or assets now owned or hereafter
acquired to secure any indebtedness, without making effective provision whereby
the Securities of such series shall be equally and ratably secured with any and
all such indebtedness and with any other indebtedness similarly entitled to be
equally and ratably secured. However, this restriction shall not apply to or
prevent the creation or existence of:

     (1)  Liens on property existing at the time of acquisition or construction
          of such property (or created within one year after completion of such
          acquisition or construction), whether by purchase, merger,
          construction or otherwise (or on the property of a Subsidiary at the
          date it became a Subsidiary), or to secure the payment of all or any
          part of the purchase price or construction cost thereof, including the
          extension of any such Liens to repairs, renewals, replacements,
          substitutions, betterments, additions, extensions and improvements
          then or thereafter made on the property subject thereto;

     (2)  any extensions, renewals or replacements (or successive extensions,
          renewals or replacements), in whole or in part of Liens permitted by
          the foregoing clause (1);

     (3)  the pledge of any bonds or other securities at any time issued under
          any of the Liens permitted by clauses (1) or (2); or

     (4)  Permitted Encumbrances.

     Further, this restriction shall not apply to or prevent the creation or
existence of leases made, or existing on property acquired, in the ordinary
course of business.

                             ARTICLE 5 - SUCCESSORS

SECTION 5.01  When Company May Merge, etc.

     Unless the Securities Resolution establishing a series otherwise provides,
the Company shall not consolidate with or merge into any Person in any
transaction in which the Company is not the survivor, or transfer all or
substantially all of its property to any Person, unless:

     (1)  the Person is organized under the laws of the United States or a State
          thereof;

     (2)  the Person assumes by supplemental indenture all the obligations of
          the Company under this Indenture, the Securities and any coupons;

     (3)  all required approvals of any regulatory body having jurisdiction over
          the transaction shall have been obtained;

                                       16

<PAGE>

     (4)  immediately after the transaction no Default exists; and

     (5)  the Company provides an Officers' Certificate and an Opinion of
          Counsel to the effect that all the provisions in this Section 5.01
          have been complied with.

     The successor shall be substituted for the Company, and thereafter all
obligations of the Company under this Indenture, the Securities and any coupons
shall terminate.

                        ARTICLE 6 - DEFAULTS AND REMEDIES

SECTION 6.01  Events of Default.

     Unless the Securities Resolution establishing a series otherwise provides,
an "Event of Default" on the series so established occurs if:

     (1)  the Company defaults in any payment of interest on any Securities of
          the series when the same becomes due and payable and the Default
          continues for a period of 60 days;

     (2)  the Company defaults in the payment of the principal of any Securities
          of the series when the same becomes due and payable at maturity or
          upon redemption, acceleration or otherwise;

     (3)  the Company defaults in the payment or satisfaction of any sinking
          fund obligation with respect to any Securities of the series as
          required by the Securities Resolution establishing such series and the
          Default continues for a period of 60 days;

     (4)  the Company defaults in the performance of any of its other agreements
          applicable to the series and the Default continues for 90 days after
          the notice specified below;

     (5)  the Company pursuant to or within the meaning of any Bankruptcy Law:

          (A)  commences a voluntary case,

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

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

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

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

          (A)  is for relief against the Company in an involuntary case,

                                       17

<PAGE>

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

          (C)  orders the liquidation of the Company,

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

     (7)  there occurs any other Event of Default provided for in the series.

     The term "Bankruptcy Law" means Title 11, U.S. Code or any similar Federal
or State law for the relief of debtors. The term "Custodian" means any receiver,
trustee, assignee, liquidator or a similar official under any Bankruptcy Law.

     A Default under clause (4) is not an Event of Default until the Trustee or
the Holders of at least 25% in principal amount of the series notify the Company
of the Default and the Company does not cure the Default within the time
specified after receipt of the notice. The notice must specify the Default,
demand that it be remedied and state that the notice is a "Notice of Default."
If Holders notify the Company of a Default, they shall notify the Trustee at the
same time.

     Unless the Securities Resolution establishing a series provides otherwise,
a Default on a series of Securities issued under this Indenture does not
constitute a Default on any other series of Securities issued under this
Indenture.

     The failure to redeem any Security subject to a Conditional Redemption is
not an Event of Default if any event on which such redemption is so conditioned
does not occur and is not waived before the scheduled redemption date.

SECTION 6.02  Acceleration.

     If an Event of Default occurs and is continuing on a series, the Trustee by
notice to the Company, or the Holders of at least 25% in principal amount of the
series by notice to the Company and the Trustee, may declare the principal of
and accrued interest on all the Securities of the series to be due and payable
immediately. Discounted Securities may provide that the amount of principal due
upon acceleration is less than the stated principal amount.

     The Holders of a majority in principal amount of the series by notice to
the Trustee may rescind an acceleration and its consequences if the rescission
would not conflict with any judgment or decree and if all existing Events of
Default on the series have been cured or waived except nonpayment of principal
or interest that has become due solely because of the acceleration.

SECTION 6.03  Other Remedies.

     If an Event of Default occurs and is continuing on a series, the Trustee
may pursue any available remedy to collect principal or interest then due on the
series, to enforce the performance of any provision applicable to the series, or
otherwise to protect the rights of the Trustee and Holders of the series.

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<PAGE>

     The Trustee may maintain a proceeding even if it does not possess any of
the Securities or coupons or does not produce any of them in the proceeding. A
delay or omission by the Trustee or any Securityholder in exercising any right
or remedy accruing upon an Event of Default shall not impair the right or remedy
or constitute a waiver of or acquiescence in the Event of Default. All remedies
are cumulative to the extent permitted by law.

SECTION 6.04  Waiver of Past Defaults.

     The Holders of a majority in principal amount of a series by notice to the
Trustee may waive an existing Default on the series and its consequences except:

     (1)  a Default in the payment of the principal of or interest on the
          series, or

     (2)  a Default in respect of a provision that under Section 9.02 cannot be
          amended without the consent of each Securityholder affected.

SECTION 6.05  Control by Majority.

     The Holders of a majority in principal amount of a series may direct the
time, method and place of conducting any proceeding for any remedy available to
the Trustee, or of exercising any trust or power conferred on the Trustee, with
respect to the series. However, the Trustee may refuse to follow any direction
that conflicts with law or this Indenture.

SECTION 6.06  Limitation on Suits.

     A Securityholder of a series may pursue a remedy with respect to the series
only if:

     (1)  the Holder gives to the Trustee notice of a continuing Event of
          Default on the series;

     (2)  the Holders of at least 25% in principal amount of the series make a
          request to the Trustee to pursue the remedy;

     (3)  such Holder or Holders offer to the Trustee indemnity satisfactory to
          the Trustee against any loss, liability or expense;

     (4)  the Trustee does not comply with the request within 60 days after
          receipt of the request and the offer of indemnity; and

     (5)  during such 60-day period the Holders of a majority in principal
          amount of the series do not give the Trustee a direction inconsistent
          with such request.

     A Securityholder may not use this Indenture to prejudice the rights of
another Securityholder or to obtain a preference or priority over another
Securityholder.

SECTION 6.07  Collection Suit by Trustee.

     If an Event of Default in payment of interest, principal or sinking fund
obligation specified in Section 6.01(1), (2) or (3) occurs and is continuing on
a series, the Trustee may

                                       19

<PAGE>

recover judgment in its own name and as trustee of an express trust against the
Company for the whole amount of principal and interest remaining unpaid on the
series.

SECTION 6.08  Priorities.

     If the Trustee collects any money for a series pursuant to this Article, it
shall pay out the money in the following order:

     First: to the Trustee for amounts due under Section 7.06;

     Second: to Securityholders of the series for amounts due and unpaid for
principal and interest, ratably, without preference or priority of any kind,
according to the amounts due and payable for principal and interest,
respectively; and

     Third: to the Company.

     The Trustee may fix a payment date for any payment to Securityholders.

                             ARTICLE 7 - TRUSTEE

SECTION 7.01  Rights of Trustee.

     (1)  The Trustee may rely on any document believed by it to be genuine and
          to have been signed or presented by the proper person. The Trustee
          need not investigate any fact or matter stated in the document.

     (2)  Before the Trustee acts or refrains from acting, it may require an
          Officers' Certificate or an Opinion of Counsel. The Trustee shall not
          be liable for any action it takes or omits to take in good faith in
          reliance on the Certificate or Opinion.

     (3)  The Trustee may act through agents and shall not be responsible for
          the misconduct or negligence of any agent appointed with due care.

     (4)  The Trustee shall not be liable for any action it takes or omits to
          take in good faith in accordance with a direction received by it
          pursuant to Section 6.05.

     (5)  The Trustee may refuse to perform any duty or exercise any right or
          power which it reasonably believes may expose it to any loss,
          liability or expense unless it receives indemnity satisfactory to it
          against such loss, liability or expense.

     (6)  The Trustee shall not be liable for interest on any money received by
          it except as the Trustee may agree with the Company. Money held in
          trust by the Trustee need not be segregated from other funds except to
          the extent required by law.

     (7)  The Trustee shall have no duty with respect to a Default unless a
          Trust Officer has received written notice of such Default.

                                       20

<PAGE>

     (8)  The Trustee shall not be liable for any action it takes or omits to
          take in good faith which it believes to be authorized and within its
          powers.

     (9)  Any Agent shall have the same rights and be protected to the same
          extent as if it were Trustee.

SECTION 7.02  Individual Rights of Trustee.

     The Trustee in its individual or any other capacity may become the owner or
pledgee of Securities or coupons and may otherwise deal with the Company or an
Affiliate with the same rights it would have if it were not Trustee. Any Agent
may do the same with like rights.

SECTION 7.03  Trustee's Disclaimer.

     The Trustee makes no representation as to the validity or adequacy of this
Indenture or the Securities or any coupons; it shall not be accountable for the
Company's use of the proceeds from the Securities; it shall not be responsible
for any statement in the Securities or any coupons; it shall not be responsible
for any overissue; it shall not be responsible for determining whether the form
and terms of any Securities or coupons were established in conformity with this
Indenture; and it shall not be responsible for determining whether any
Securities were issued in accordance with this Indenture.

SECTION 7.04  Notice of Defaults.

     If a Default occurs and is continuing on a series and if it is known to the
Trustee, the Trustee shall mail a notice of the Default within 90 days after it
occurs to Holders of Registered Securities of the series. Except in the case of
a Default in payment on a series, the Trustee may withhold the notice if and so
long as a committee of its Trust Officers in good faith determines that
withholding the notice is in the interest of Holders of the series. The Trustee
shall withhold notice of a Default described in Section 6.01(4) until at least
90 days after it occurs.

SECTION 7.05  Reports by Trustee to Holders.

     Any report required by TIA Section 313(a) to be mailed to Securityholders
shall be mailed by the Trustee on or before July 15 of each year.

     A copy of each report at the time of its mailing to Securityholders
shall be filed with the SEC and each stock  exchange on which any Securities are
listed. The Company shall notify the Trustee when any Securities are listed on a
stock exchange.

SECTION 7.06  Compensation and Indemnity.

     The Company shall pay to the Trustee from time to time reasonable
compensation for its services. The Trustee's compensation shall not be limited
by any law on compensation of a trustee of an express trust. The Company shall
reimburse the Trustee upon request for all reasonable out-of-pocket expenses
incurred by it. Such expenses shall include the reasonable compensation and
expenses of the Trustee's agents and counsel.

                                       21

<PAGE>

     The Company shall indemnify the Trustee (including its officers, directors
and employees) against any loss or liability incurred by it. The Trustee shall
notify the Company promptly of any claim for which it may seek indemnity. The
Company shall defend the claim and the Trustee shall cooperate in the defense.
The Trustee may have separate counsel and the Company shall pay the reasonable
fees and expenses of such counsel. The Company need not pay for any settlement
made without its consent.

     The Company need not reimburse any expense or indemnify against any loss or
liability incurred by the Trustee through negligence, bad faith or willful
misconduct.

     To secure the Company's payment obligations in this Section, the Trustee
shall have a Lien prior to the Securities and any coupons on all money or
property held or collected by the Trustee, except that held in trust to pay
principal or interest on particular Securities.

     When the Trustee incurs expenses or renders services after an Event of
Default specified in Section 6.01(5) or (6) occurs, such expenses and the
compensation for such services are intended to constitute expenses of
administration under any Bankruptcy Law.

     The provisions of this Section shall survive any termination or discharge
of this Indenture (including without limitation any termination under any
Bankruptcy Law) and the resignation or removal of the Trustee.

SECTION 7.07  Replacement of Trustee.

     A resignation or removal of the Trustee and appointment of a successor
Trustee shall become effective only upon the successor Trustee's acceptance of
appointment as provided in this Section.

     The Trustee may resign by so notifying the Company. The Holders of a
majority in principal amount of the Securities may remove the Trustee by so
notifying the Trustee and may appoint a successor Trustee with the Company's
consent.

     The Company may remove the Trustee if:

     (1)  the Trustee fails to comply with TIA Section 310(a) or TIA Section
          310(b) or with Section 7.09;

     (2)  the Trustee is adjudged a bankrupt or an insolvent;

     (3)  a Custodian or other public officer takes charge of the Trustee or its
          property;

     (4)  the Trustee becomes incapable of acting; or

     (5)  an event of the kind described in Section 6.01(5) or (6) occurs with
          respect to the Trustee.

                                       22

<PAGE>

     The Company also may remove the Trustee with or without cause if the
Company so notifies the Trustee three months in advance and if no Default occurs
or is continuing during the three-month period.

     If the Trustee resigns or is removed or if a vacancy exists in the office
of Trustee for any reason, the Company shall promptly appoint a successor
Trustee.

     If a successor Trustee does not take office within 30 days after the
retiring Trustee resigns or is removed, the retiring Trustee, the Company or the
Holders of a majority in principal amount of the Securities may petition any
court of competent jurisdiction for the appointment of a successor Trustee.

     If the Trustee fails to comply with TIA Section 310(a) or TIA Section
310(b) or with Section 7.09, any Securityholder may petition any court of
competent jurisdiction for the removal of the Trustee and the appointment of a
successor Trustee.

     A successor Trustee shall deliver a written acceptance of its appointment
to the retiring Trustee and to the Company. Thereupon the resignation or removal
of the retiring Trustee shall become effective, and the successor Trustee shall
have all the rights, powers and duties of the Trustee under this Indenture. The
successor Trustee shall mail a notice of its succession to Holders of Registered
Securities. The retiring Trustee shall promptly transfer all property held by it
as Trustee to the successor Trustee, subject to the Lien provided for in Section
7.06.

SECTION 7.08  Successor Trustee by Merger, etc.

     If the Trustee consolidates, merges or converts into, or transfers all or
substantially all of its corporate trust business to, another corporation, the
successor corporation without any further act shall be the successor Trustee.

SECTION 7.09  Trustee's Capital and Surplus.

     The Trustee at all times shall have a combined capital and surplus of at
least $10,000,000 as set forth in its most recent published report of condition.

                       ARTICLE 8 - DISCHARGE OF INDENTURE

SECTION 8.01  Defeasance.

     Securities of a series may be defeased in accordance with their terms and,
unless the Securities Resolution establishing the series otherwise provides, in
accordance with this Article.

     The Company at any time may terminate as to a series all of its obligations
under this Indenture, the Securities of a series and any related coupons ("legal
defeasance option"). The Company at any time may terminate as to a series its
obligations, if any, under Section 4.07 and any other restrictive covenants
which may be applicable to a particular series ("covenant defeasance option").
However, in the case of the legal defeasance option, the Company's

                                       23

<PAGE>

obligations in Sections 2.03, 2.04, 2.05, 2.06, 2.07, 2.08, 7.06, 7.07 and 8.04
shall survive until the Securities of the series are no longer outstanding;
thereafter the Company's obligations in Section 7.06 shall survive.

     The Company may exercise its legal defeasance option notwithstanding its
prior exercise of its covenant defeasance option. If the Company exercises its
legal defeasance option, a series may not be accelerated because of an Event of
Default. If the Company exercises its covenant defeasance option, a series may
not be accelerated by reference to Section 4.07 or any other restrictive
covenants which may be applicable to a particular series so defeased under the
terms of the series.

     The Trustee upon request shall acknowledge in writing the discharge of
those obligations that the Company terminates.

SECTION 8.02  Conditions to Defeasance.

     The Company may exercise as to a series its legal defeasance option or its
covenant defeasance option if:

     (1)  the Company irrevocably deposits in trust with the Trustee or another
          trustee money or U.S. Government Obligations;

     (2)  the Company delivers to the Trustee a certificate from a nationally
          recognized firm of independent accountants expressing their opinion
          that the payments of principal and interest when due on the deposited
          U.S. Government Obligations without reinvestment plus any deposited
          money without investment will provide cash at such times and in such
          amounts as will be sufficient to pay principal and interest when due
          on all the Securities of the series to maturity or redemption, as the
          case may be;

     (3)  immediately after the deposit no Default exists;

     (4)  the deposit does not constitute a default under any other agreement
          binding on the Company;

     (5)  the deposit does not cause the Trustee to have a conflicting interest
          under TIA Section 310(a) or TIA Section 310(b) as to another series;

     (6)  the Company delivers to the Trustee an Opinion of Counsel to the
          effect that Holders of the series will not recognize income, gain or
          loss for Federal income tax purposes as a result of the defeasance;
          and

     (7)  91 days pass after the deposit is made and during the 91-day period no
          Default specified in Section 6.01(5) or (6) occurs that is continuing
          at the end of the period.

     Before or after a deposit the Company may make arrangements satisfactory to
the Trustee for the redemption of Securities at a future date in accordance with
Article 3.

                                       24

<PAGE>

     "U.S. Government Obligations" means securities which are direct obligations
of (i) the United States or (ii) an agency or instrumentality of the United
States, the payment of which is unconditionally guaranteed by the United States,
which, in either case, have the full faith and credit of the United States
pledged for payment and are not callable at the issuer's option, or certificates
representing an ownership interest in such obligations.

SECTION 8.03  Application of Trust Money.

     The Trustee shall hold in trust money or U.S. Government Obligations
deposited with it pursuant to Section 8.02. It shall apply the deposited money
and the money from U.S. Government Obligations through the Paying Agent and in
accordance with this Indenture to the payment of principal and interest on
Securities of the defeased series.

SECTION 8.04  Repayment to Company.

     The Trustee and the Paying Agent shall promptly turn over to the Company
upon request any excess money or securities held by them at any time.

     The Trustee and the Paying Agent shall pay to the Company upon request any
money held by them for the payment of principal or interest that remains
unclaimed for two years. After payment to the Company, Securityholders entitled
to the money must look to the Company for payment as unsecured general creditors
unless an abandoned property law designates another person.

                       ARTICLE 9 - AMENDMENTS AND WAIVERS

SECTION 9.01  Without Consent of Holders.

     The Company and the Trustee may amend this Indenture, the Securities or any
coupons without the consent of any Securityholder:

     (1)  to cure any ambiguity, omission, defect or inconsistency;

     (2)  to comply with Article 5;

     (3)  to provide that specific provisions of this Indenture shall not apply
          to a series not previously issued;

     (4)  to create a series and establish its terms;

     (5)  to provide for a separate Trustee for one or more series; or

     (6)  to make any change that does not materially adversely affect the
          rights of any Securityholder.

                                       25

<PAGE>

SECTION 9.02  With Consent of Holders.

     The Company and the Trustee may amend this Indenture, the Securities or any
coupons with the written consent of the Holders of a majority in principal
amount of the Securities of all series affected by the amendment voting as one
class. However, without the consent of each Securityholder affected, an
amendment under this Section may not:

     (1)  reduce the amount of Securities whose Holders must consent to an
          amendment;

     (2)  reduce the interest on or change the time for payment of interest on
          any Security;

     (3)  change the fixed maturity of any Security;

     (4)  reduce the principal of any non-Discounted Security or reduce the
          amount of principal of any Discounted Security that would be due upon
          an acceleration thereof;

     (5)  change the currency in which principal or interest on a Security is
          payable; or

     (6)  make any change in Section 6.04 or 9.02, except to increase the amount
          of Securities whose Holders must consent to an amendment or waiver or
          to provide that other provisions of this Indenture cannot be amended
          or waived without the consent of each Securityholder affected thereby.

     An amendment of a provision included solely for the benefit of one or more
series does not affect Securityholders of any other series.

     Securityholders need not consent to the exact text of a proposed amendment
or waiver; it is sufficient if they consent to the substance thereof.

SECTION 9.03  Compliance with Trust Indenture Act.

     Every amendment pursuant to Section 9.01 or 9.02 shall be set forth in a
supplemental indenture that complies with the TIA as then in effect.

     If a provision of the TIA requires or permits a provision of this Indenture
and the TIA provision is amended, then the Indenture provision shall be
automatically amended to like effect.

SECTION 9.04  Effect of Consents.

     An amendment or waiver becomes effective in accordance with its terms and
thereafter binds every Securityholder entitled to consent to it.

     A consent to an amendment or waiver by a Holder of a Security is a
continuing consent by the Holder and every subsequent Holder of a Security that
evidences the same debt as the consenting Holder's Security. Any Holder or
subsequent Holder may revoke the consent as to his Security if the Trustee
receives notice of the revocation before the amendment or waiver becomes
effective.

                                       26

<PAGE>

     The Company may fix a record date for the determination of Holders of
Registered Securities entitled to give a consent. The record date shall not be
less than 10 nor more than 60 days prior to the first written solicitation of
Securityholders.

SECTION 9.05  Notation on or Exchange of Securities.

     The Company or the Trustee may place an appropriate notation about an
amendment or waiver on any Security thereafter authenticated. The Company may
issue in exchange for affected Securities new Securities that reflect the
amendment or waiver.

SECTION 9.06  Trustee Protected.

     The Trustee need not sign any supplemental indenture that adversely affects
its rights. The Trustee shall be entitled to receive, and shall be fully
protected in relying upon, an Opinion of Counsel and an Officers' Certificate
each stating that the execution of any amendment or supplement or waiver
authorized pursuant to this Article is authorized or permitted by this
Indenture, and that such amendment or supplement or waiver constitutes the
legal, valid and binding obligation of the Company.

                           ARTICLE 10 - MISCELLANEOUS

SECTION 10.01 Trust Indenture Act.

     The provisions of TIA Sections 310 through 317 that impose duties on any
person (including the provisions automatically deemed included herein unless
expressly excluded by this Indenture) are a part of and govern this Indenture,
whether or not expressly set forth herein.

     If any provision of this Indenture limits, qualifies or conflicts with
another provision which is required to be included in this Indenture by the TIA,
the required provision shall control.

SECTION 10.02 Notices.

     Any notice by one party to another is duly given if in writing and
delivered in person, sent by facsimile transmission confirmed by mail or mailed
by first-class mail to the other's address shown below:

                                       27

<PAGE>

              Company:  Wisconsin Gas Company
                        231 West Michigan Street
                        P.O. Box 2046
                        Milwaukee, WI  53201
                        Attention:  Corporate Secretary

              Trustee:  U.S. Bank National Association
                        1555 N. RiverCenter Dr., Suite 301
                        Milwaukee, WI  53212
                        Attention:  Corporate Trust Department

     A party by notice to the other parties may designate additional or
different addresses for subsequent notices.

     Any notice mailed to a Securityholder shall be mailed to his address shown
on the register kept by the Transfer Agent or on the list referred to in Section
2.06. Failure to mail a notice to a Securityholder or any defect in a notice
mailed to a Securityholder shall not affect the sufficiency of the notice mailed
to other Securityholders or the sufficiency of any published notice.

     If a notice is mailed in the manner provided above within the time
prescribed, it is duly given, whether or not the addressee receives it.

     If the Company mails a notice to Securityholders, it shall mail a copy to
the Trustee and each Agent at the same time.

     If in the Company's opinion it is impractical to mail a notice required to
be mailed or to publish a notice required to be published, the Company may give
such substitute notice as the Trustee approves. Failure to publish a notice as
required or any defect in it shall not affect the sufficiency of any mailed
notice.

     All notices shall be in the English language, except that any published
notice may be in an official language of the country of publication.

     A "notice" includes any communication required by this Indenture.

SECTION 10.03 Certificate and Opinion as to Conditions Precedent.

     Upon any request or application by the Company to the Trustee to take any
action under this Indenture, the Company shall if so requested furnish to the
Trustee:

     (1)  an Officers' Certificate stating that, in the opinion of the signers,
          all conditions precedent, if any, provided for in this Indenture
          relating to the proposed action have been complied with; and

     (2)  an Opinion of Counsel stating that, in the opinion of such counsel,
          all such conditions precedent have been complied with.

                                       28

<PAGE>

SECTION 10.04 Statements Required in Certificate or Opinion.

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

     (1)  a statement that the person making such certificate or opinion has
          read such covenant or condition;

     (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 such person, he has made such
          examination or investigation as is necessary to enable him 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 or not, in the opinion of such person, such
          condition or covenant has been complied with.

SECTION 10.05 Rules by Company and Agents.

     The Company may make reasonable rules for action by or a meeting of
Securityholders. An Agent may make reasonable rules and set reasonable
requirements for its functions.

SECTION 10.06 Legal Holidays.

     A "Legal Holiday" is a Saturday, a Sunday or a day on which banking
institutions are not required to be open. If a payment date is a Legal Holiday
at a place of payment, unless the Securities Resolution establishing a series
otherwise provides with respect to Securities of the series, payment may be made
at that place on the next succeeding day that is not a Legal Holiday, and no
interest shall accrue for the intervening period.

SECTION 10.07 No Recourse Against Others.

     All liability described in the Securities of any director, officer,
employee or stockholder, as such, of the Company is waived and released.

SECTION 10.08 Duplicate Originals.

     The parties may sign any number of copies of this Indenture. One signed
copy is enough to prove this Indenture.

SECTION 10.09 Governing Law.

     The laws of the State of Wisconsin shall govern this Indenture, the
Securities and any coupons, unless Federal law governs.

                                       29

<PAGE>

                                   SIGNATURES


Dated as of ______________, 2003         WISCONSIN GAS COMPANY


                                         By:
                                            ------------------------------------
                                            Name:
                                                 -------------------------------
                                            Title:
                                                  ------------------------------


Dated as of ______________, 2003         U.S. BANK NATIONAL ASSOCIATION


                                         By:
                                            ------------------------------------
                                            Name:
                                                 -------------------------------
                                            Title:
                                                  ------------------------------


                                       30

<PAGE>

                                    EXHIBIT A

                          A Form of Registered Security

No._____________                                                 $______________

                              WISCONSIN GAS COMPANY
                               [Title of Security]

WISCONSIN GAS COMPANY

promises to pay to ________________________________________

or registered assigns
the principal sum of _____________________________________ Dollars
on __________, 20___


Interest Payment Dates:
                       ---------------------------
Record Dates:
                       ---------------------------


                                         Dated:


U.S. BANK NATIONAL ASSOCIATION           WISCONSIN GAS COMPANY
Transfer Agent and Paying Agent

                                         By:
                                            ------------------------------------
                                               (Title of Authorized Officer)

Authenticated:                           (CORPORATE SEAL)

U.S. BANK NATIONAL ASSOCIATION
Registrar, by


--------------------------------         ---------------------------------------
Authorized Signature                     [Assistant] Secretary

                                       A-1

<PAGE>

                              WISCONSIN GAS COMPANY
                               [Title of Security]

1.   Interest.(1)

     Wisconsin Gas Company (the "Company"), a Wisconsin corporation, promises to
     pay interest on the principal amount of this Security at the rate per annum
     shown above. The Company will pay interest semiannually on
     _________________ and _________________ of each year commencing
     ________________, 20__. 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 _________________, 20__. Interest will be computed on the
     basis of a 360-day year of twelve 30-day months.

2.   Method of Payment.(2)

     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.

3.   Securities Agents.(2A)

     Initially, U.S. Bank National Association 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.

4.   Indenture.

     The Company issued the securities of this series (the "Securities") under
     an Indenture dated as of ________________, 2003 (the "Indenture") between
     the Company and U.S. Bank National Association (the "Trustee"). The terms
     of the Securities include those stated in the Indenture and in the
     Securities Resolution 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
     Securities Resolution and such Act for a statement of such terms.

5.   Optional Redemption.(3)

     On or after _____________, 20__, the Company may redeem all the Securities
     at any time or some of them from time to time at the following redemption
     prices (expressed in percentages of principal amount), plus accrued
     interest to the redemption date.

                                       A-2

<PAGE>

     If redeemed during the 12-month period beginning _______________,

     Year       Percentage      Year    Percentage




     and thereafter at 100%.

6.   Mandatory Redemption.(4)

     The Company will redeem $____________ principal amount of Securities on
     _________________________ and on each _______________ thereafter through
     ____________________ at a redemption price of 100% of principal amount,
     plus accrued interest to the redemption date.(5) The Company may reduce the
     principal amount of Securities to be redeemed pursuant to this paragraph by
     subtracting 100% of the principal amount (excluding premium) of any
     Securities (i) that the Company has acquired or that the Company has
     redeemed other than pursuant to this paragraph and (ii) that the Company
     has delivered to the Registrar for cancellation. The Company may so
     subtract the same Security only once.

7.   Additional Optional Redemption.(6)

     In addition to redemptions pursuant to the above paragraph(s), the Company
     may redeem not more than $____________ principal amount of Securities on
     ________________________ and on each __________________ thereafter through
     __________________ at a redemption price of 100% of principal amount, plus
     accrued interest to the redemption date.

8.   Notice of Redemption.(7)

     Notice of redemption will be mailed at least [30 days but not more than 60
     days] before the redemption date to each holder of Securities to be
     redeemed at such holder's registered address.

     A notice of redemption may provide that it is subject to the occurrence of
     any event before the date fixed for such redemption as described in such
     notice ("Conditional Redemption") and such notice of Conditional Redemption
     shall be of no effect unless all such conditions to the redemption have
     occurred before such date or have been waived by the Company.

9.   Denominations, Transfer, Exchange.

     The Securities are in registered form without coupons in denominations of
     $1,000(8) 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

                                       A-3

<PAGE>

     holder, among other things, to furnish appropriate endorsements and
     transfer documents and to pay any taxes and fees required by law or the
     Indenture. The Transfer Agent need not exchange or register the transfer of
     any Security or portion of a Security selected for redemption. Also, it
     need not exchange or register the transfer of any Securities for a period
     of 15 days before a selection of Securities to be redeemed.

10.  Persons Deemed Owners.

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

11.  Amendments and Waivers.

     Subject to certain exceptions, the Indenture or the Securities may be
     amended with the consent of the holders of a majority in principal amount
     of the securities of all series affected by the amendment.(9)

     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.

12.  Restrictive Covenants.(10)

     The Securities are unsecured general obligations of the Company [initially]
     limited to $____________ principal amount. [The Company may from time to
     time without notice to, or the consent of, the holders of the Securities,
     create and issue further securities of the same series, equal in rank to
     the Securities in all respects (or in all respects except for the payment
     of interest accruing prior to the issue date of the new securities or
     except for the first payment of interest following the issue date of the
     new securities) so that the new securities may be consolidated and form a
     single series with the Securities and have the same terms as to status,
     redemption or otherwise as the Securities.] The Indenture does not limit
     other unsecured debt. Section 4.07 of the Indenture, which if applicable
     limits certain mortgages and other liens, [will] [will not] apply with
     respect to the Securities. [The limitations are subject to a number of
     important qualifications and exceptions.]

13.  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.

14.  Defeasance Prior to Redemption or Maturity.(11)

     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

                                       A-4

<PAGE>

     on the Securities to redemption or 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.

15.  Defaults and Remedies.

     An Event of Default(12) includes: default for 60 days in payment of
     interest on the Securities; default in payment of principal on the
     Securities; default for 60 days in the payment or satisfaction of any
     sinking fund obligation with respect to 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; certain events of
     bankruptcy or insolvency; and any other Event of Default provided for in
     the series. 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(13) 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.

16.  Trustee Dealings with Company.

     U.S. Bank National Association, the Trustee under the Indenture, 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.

17.  No Recourse Against Others.

     A director, officer, employee or stockholder, 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.

18.  Authentication.

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

19.  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

                                       A-5

<PAGE>

     (=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 Securities Resolution[, which contains
the text of this Security in larger type]. Requests may be made to: Corporate
Secretary, Wisconsin Gas Company, 231 West Michigan Street, P.O. Box 2046,
Milwaukee, WI 53201.

                                       A-6

<PAGE>

                                    EXHIBIT B

                            A Form of Bearer Security

No._____________                                                 $______________

                              WISCONSIN GAS COMPANY
                               [Title of Security]

WISCONSIN GAS COMPANY

promises to pay to ________________________________________

or registered assigns
the principal sum of ______________________________________ Dollars
on __________, 20 ___


Interest Payment Dates:
                       ---------------------------
Record Dates:
                       ---------------------------


                                         Dated:

U.S. BANK NATIONAL ASSOCIATION           WISCONSIN GAS COMPANY
Transfer Agent and Paying Agent
                                         By:
                                            ------------------------------------
                                               (Title of Authorized Officer)

Authenticated:                           (CORPORATE SEAL)

U.S. BANK NATIONAL ASSOCIATION
Registrar, by


--------------------------------         ---------------------------------------
Authorized Signature                     [Assistant] Secretary

                                       B-1

<PAGE>

                              WISCONSIN GAS COMPANY
                               [Title of Security]

1.   Interest.(1)

     Wisconsin Gas Company (the "Company"), a Wisconsin corporation, promises to
     pay to bearer interest on the principal amount of this Security at the rate
     per annum shown above. The Company will pay interest semiannually on
     __________________________ and __________________________ of each year
     commencing _________________, 20__. 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 ______________, 20__. Interest will be
     computed on the basis of a 360-day year of twelve 30-day months.

2.   Method of Payment.(2)

     Holders must surrender Securities and any coupons to a Paying Agent to
     collect principal and interest 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.

3.   Securities Agents.(2A)

     Initially, U.S. Bank National Association will act as Transfer Agent,
     Paying 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.

4.   Indenture.

     The Company issued the securities of this series (the "Securities") under
     an Indenture dated as of ________________, 2003 (the "Indenture") between
     the Company and U.S. Bank National Association (the "Trustee"). The terms
     of the Securities include those stated in the Indenture and the Securities
     Resolution establishing the series 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 Securities Resolution
     and such Act for a statement of such terms.

5.   Optional Redemption.(3)

     On or after ____________, 20__, the Company may redeem all the Securities
     at any time or some of them from time to time at the following redemption
     prices (expressed in percentages of principal amount), plus accrued
     interest to the redemption date.

                                       B-2

<PAGE>

     If redeemed during the 12-month period beginning ___________________,

     Year       Percentage       Year   Percentage




     and thereafter at 100%.

6.   Mandatory Redemption.(4)

     The Company will redeem $_________ principal amount of Securities on
     __________________ and on each __________________ thereafter through
     _________________ at a redemption price of 100% of principal amount, plus
     accrued interest to the redemption date(5). The Company may reduce the
     principal amount of Securities to be redeemed pursuant to this paragraph by
     subtracting 100% of the principal amount (excluding premium) of any
     Securities (i) that the Company has acquired or that the Company has
     redeemed other than pursuant to this paragraph and (ii) that the Company
     has delivered to the Registrar for cancellation. The Company may so
     subtract the same Security only once.

7.   Additional Optional Redemption.(6)

     In addition to redemptions pursuant to the above paragraph(s), the Company
     may redeem not more than $____________ principal amount of Securities on
     __________________ and on each __________________ thereafter through
     __________________ at a redemption price of 100% of principal amount, plus
     accrued interest to the redemption date.

8.   Notice of Redemption.(7)

     Notice of redemption will be published once in an Authorized Newspaper in
     the City of New York and if the Securities are listed on any stock exchange
     located outside the United States and such stock exchange so requires, in
     any other required city outside the United States at least [30 days but not
     more than 60 days] before the redemption date. Notice of redemption also
     will be mailed to holders who have filed their names and addresses with the
     Transfer Agent within the two preceding years. Holders of Securities may
     miss important notices if they fail to maintain their names and addresses
     with the Transfer Agent.

     A notice of redemption may provide that it is subject to the occurrence of
     any event before the date fixed for such redemption as described in such
     notice ("Conditional Redemption") and such notice of Conditional Redemption
     shall be of no effect unless all such conditions to the redemption have
     occurred before such date or have been waived by the Company.

                                       B-3

<PAGE>

9.   Denominations, Transfer, Exchange.

     The Securities are in bearer form with coupons in denominations of
     $5,000(8) and whole multiples of $5,000. The Securities may be transferred
     by delivery and exchanged as provided in the Indenture. Upon an exchange,
     the Transfer Agent may require a holder, among other things, to furnish
     appropriate documents and to pay any taxes and fees required by law or the
     Indenture. The Transfer Agent need not exchange any Security or portion of
     a Security selected for redemption. Also, it need not exchange any
     Securities for a period of 15 days before a selection of Securities to be
     redeemed.

10.  Persons Deemed Owners.

     The holder of a Security or coupon may be treated as its owner for all
     purposes.

11.  Amendments and Waivers.

     Subject to certain exceptions, the Indenture or the Securities may be
     amended with the consent of the holders of a majority in principal amount
     of the securities of all series affected by the amendment.(9)

     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.

12.  Restrictive Covenants.(10)

     The Securities are unsecured general obligations of the Company [initially]
     limited to $____________ principal amount. [The Company may from time to
     time without notice to, or the consent of, the holders of the Securities,
     create and issue further securities of the same series, equal in rank to
     the Securities in all respects (or in all respects except for the payment
     of interest accruing prior to the issue date of the new securities or
     except for the first payment of interest following the issue date of the
     new securities) so that the new securities may be consolidated and form a
     single series with the Securities and have the same terms as to status,
     redemption or otherwise as the Securities.] The Indenture does not limit
     other unsecured debt. Section 4.07 of the Indenture, which if applicable
     limits certain mortgages and other liens, [will] [will not] apply with
     respect to the Securities. [The limitations are subject to a number of
     important qualifications and exceptions.]

13.  Successors.

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

                                       B-4

<PAGE>

14.  Defeasance Prior to Redemption or Maturity.(11)

     Subject to certain conditions, the Company at any time may terminate some
     or all of its obligations under the Securities, any coupons 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
     redemption or 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.

15.  Defaults and Remedies.

     An Event of Default(12) includes: default for 60 days in payment of
     interest on the Securities; default in payment of principal on the
     Securities; default for 60 days in the payment or satisfaction of any
     sinking fund obligation with respect to 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; certain events of
     bankruptcy or insolvency; and any other Event of Default provided for in
     the series. 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(13) 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.

16.  Trustee Dealings with Company.

     U.S. Bank National Association, the Trustee under the Indenture, 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.

17.  No Recourse Against Others.

     A director, officer, employee or stockholder, 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.

18.  Authentication.

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

                                       B-5

<PAGE>

19.  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 Securities Resolution[, which contains
the text of this Security in larger type]. Requests may be made to: Corporate
Secretary, Wisconsin Gas Company, 231 West Michigan Street, P.O. Box 2046,
Milwaukee, WI 53201.

                                       B-6

<PAGE>

                                [FACE OF COUPON]

                                                 ...............................

                                                 [$]............................

                                                 Due............................

                              WISCONSIN GAS COMPANY
                               [Title of Security]

     Unless the Security attached to this coupon has been called for redemption,
Wisconsin Gas Company (the "Company") will pay to bearer, upon surrender, the
amount shown hereon when due. This coupon may be surrendered for payment to any
Paying Agent listed on the back of this coupon unless the Company has replaced
such Agent. Payment may be made by check. This coupon represents six months'
interest.

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

                                         By:
                                            ------------------------------------

                               [REVERSE OF COUPON]

                                  PAYING AGENTS

                                       B-7

<PAGE>

                            NOTES TO EXHIBITS A AND B

(1)   If the Security is not to bear interest at a fixed rate per annum, insert
      a description of the manner in which the rate of interest is to be
      determined. If the Security is not to bear interest prior to maturity, so
      state.

(2)   If the method or currency of payment is different, insert a statement
      thereof.

(2A)  As is done in Section 2.03 of the Indenture, the Trustee must be appointed
      Registrar under Section 182.23, Wis. Stats., in order for Officers'
      signatures on Securities and the corporate seal to be facsimiles.

(3)   Revise and complete if and as applicable. If the Security is to be subject
      to a nonrefunding restriction, insert a brief summary thereof. If the
      redemption is to be subject to a condition, insert a brief summary
      thereof. If applicable, insert make-whole call provisions as provided in
      the Securities Resolution.

(4)   If applicable.

(5)   If the Security is a Discounted Security, insert amount to be redeemed or
      method of calculating such amount.

(6)   If applicable. Also insert, if applicable, provisions for repayment of
      Securities at the option of the Securityholder.

(7)   If applicable. Revise as appropriate if the Securities Resolution
      specifies a different notice requirement. If the Company may condition
      such redemption on the happening of a stated event, in which case the
      notice will so provide, insert a brief summary thereof.

(8)   If applicable. Insert additional or different denominations.

(9)   If different terms apply, insert a brief summary thereof.

(10)  If applicable. If the Security is to have the benefit of additional or
      different covenants, insert a brief summary thereof.

(11)  If applicable. If different defeasance terms apply, insert a brief summary
      thereof.

(12)  If additional or different Events of Default apply, insert a brief summary
      thereof.

(13)  If the Security is a Discounted Security, set forth the amount due and
      payable upon an Event of Default.

Note: U.S. tax law may require certain legends on Discounted and Bearer
      Securities.

<PAGE>

                                    EXHIBIT C

                                 ASSIGNMENT FORM

                To assign this Security, fill in the form below:

                  I or we assign and transfer this Security to

                _________________________________________________
                :                                               :
                :                                               :
                _________________________________________________
                  (Insert assignee's soc. sec. or tax I.D. no.)
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
________________________________________________________________________________
              (Print or type assignee's name, address and zip code)

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(s)
                                                 appear(s) on the other side of
                                                 this Security)


Signature(s) guaranteed by:
                           -----------------------------------------------------
                           (All signatures must be guaranteed by an "eligible
                           guarantor institution" as defined by Rule 17Ad-15 of
                           the Securities Exchange Act of 1934, as amended)

                                     C-1