Exhibit 4-QQQ

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THE CINCINNATI GAS & ELECTRIC COMPANY

and

THE BANK OF NEW YORK,
                                         
           Trustee

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Thirty-ninth Supplemental Indenture

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Dated as of September 1, 2002

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THE CINCINNATI GAS & ELECTRIC COMPANY
Thirty-ninth Supplemental Indenture
Dated as of September 1, 2002

TABLE OF CONTENTS

|                                                                                                                            |  |                                                                                  |  | Page
|--------------------------------------------------------------------------------------------------------------------------- |  | -------------------------------------------------------------------------------- |  | ----
|Parties                                                                                                                     |  | 1                                                                               
|Recitals                                                                                                                    |  | 1                                                                               
|Form of Bonds of Series Due 2037                                                                                            |  | 2                                                                               
|Form of Trustee's Certificate on Bonds, Series Due 2037                                                                     |  | 5                                                                               
|ARTICLE ONE
BONDS OF SERIES DUE 2037 AND ISSUE THEREOF                                                                     
|Section 1.                                                                                                                  |  | Series and Form of Bonds of Series Due 2037                                      |  | 6   
|Section 2.                                                                                                                  |  | Issue of Bonds of Series Due 2037                                                |  | 6   
|Section 3.                                                                                                                  |  | Dates, Interest Rate, etc., of Bonds of Series Due 2037                          |  | 6   
|Section 4.                                                                                                                  |  | Fully Registered Bond; Transfer Restrictions; Denominations                      |  | 6   
|Section 5.                                                                                                                  |  | Interest Payments; Interest for Purposes of Section 5 of Article Five            |  | 7   
|Section 6.                                                                                                                  |  | Redemption of Bonds of Series Due 2037                                           |  | 7   
|Section 7.                                                                                                                  |  | Absence of Maintenance and Replacement Fund                                      |  | 7   
|ARTICLE TWO
COVENANTS OF THE COMPANY                                                                                       
|Section 1.                                                                                                                  |  | Confirmation of Covenants by Company in First Mortgage                           |  | 7   
|Section 2.                                                                                                                  |  | Covenants with Respect to Subsidiaries                                           |  | 7   
|ARTICLE THREE
AMENDMENT OF ARTICLE ONE, ARTICLE FIVE, ARTICLE ELEVEN,
AND ARTICLE EIGHTEEN OF THE FIRST MORTGAGE AS AMENDED
|Section 1.                                                                                                                  |  | Amendment to Section 5 of Article One                                            |  | 8   
|Section 2.                                                                                                                  |  | Amendment to Section 2 of Article Eleven                                         |  | 8   
|Section 3.                                                                                                                  |  | Amendment to Section 3 of Article Five                                           |  | 8   
|Section 4.                                                                                                                  |  | Amendment to Section 2 of Article Eighteen                                       |  | 8   
|ARTICLE FOUR
MISCELLANEOUS                                                                                                 
|Section 1.                                                                                                                  |  | Thirty-ninth Supplemental Indenture to Form Part of First Mortgage               |  | 9   
|Section 2.                                                                                                                  |  | Definitions in First Mortgage Shall Apply to Thirty-ninth
Supplemental Indenture |  | 9   
|Section 3.                                                                                                                  |  | Execution in Counterparts                                                        |  | 9   

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THIRTY-NINTH SUPPLEMENTAL INDENTURE, dated as of September 1, 2002, between The Cincinnati Gas & Electric Company, a corporation of the State of Ohio (the "Company"), and
The Bank of New York, a New York banking corporation (the "Trustee"), as Trustee (formerly Irving Trust Company).

WHEREAS,
the Company has executed and delivered to the Trustee a certain Indenture, dated as of August 1, 1936 (the "First Mortgage"), to secure the payment of the principal of
and interest on an issue of bonds of the Company, unlimited in aggregate principal amount (the Bonds);

WHEREAS
,Article Two of the First Mortgage provides that the Bonds may be issued in series, and Article Eighteen of the First Mortgage as amended provides that the Company and the
Trustee may from time to time enter into one or more indentures supplemental to the First Mortgage for the purpose of establishing the terms and provisions of any series of Bonds other than the
initial series;

WHEREAS,
the Company and the Trustee have amended and supplemented the First Mortgage by means of thirty-eight supplemental indentures (the "First Mortgage as amended") under the Thirty-
third, Thirty-fourth, Thirty-fifth and Thirty-sixth of which there are Bonds now outstanding;

WHEREAS,
the Company, pursuant to resolutions duly adopted by its Board of Directors at a duly called and held meeting, has approved the form, terms, and provisions of this Thirty-ninth
Supplemental Indenture and authorized its execution for the purpose of creating under the First Mortgage as amended and this Thirty-ninth Supplemental Indenture a new series of First Mortgage Bonds of
Series Due 2037, which bonds are to be substantially in the following form, with appropriate omissions, insertions, and variations as in the First Mortgage as amended and in this Thirty-ninth
Supplemental Indenture provided or permitted:

[THE
REMAINDER OF THIS PAGE HAS BEEN LEFT BLANK INTENTIONALLY.]

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[FORM
OF BOND OF SERIES DUE 2037]

THE
HOLDER OF THIS BOND BY ACCEPTANCE HEREOF AGREES TO RESTRICTIONS ON TRANSFER, TO WAIVERS OF CERTAIN RIGHTS OF EXCHANGE, AND TO INDEMNIFICATION PROVISIONS AS SET FORTH BELOW. IN
ADDITION, THE BOND REPRESENTED BY THIS CERTIFICATE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933 AND SUCH BOND MAY NOT BE TRANSFERRED WITHOUT COMPLIANCE WITH APPLICABLE SECURITIES LAWS.

THIS
BOND IS NOT TRANSFERABLE EXCEPT TO A SUCCESSOR TO AMBAC ASSURANCE CORPORATION UNDER THE INSURANCE AGREEMENT DATED AS OF SEPTEMBER 1, 2002 BETWEEN AMBAC ASSURANCE CORPORATION AND THE
CINCINNATI GAS & ELECTYRIC COMPANY.

|No. |  |  | $ | 
|--- |  |  | - | 

THE CINCINNATI GAS & ELECTRIC COMPANY

FIRST MORTGAGE BOND
SERIES DUE 2037

Due September 1, 2037

THE CINCINNATI GAS & ELECTRIC COMPANY, a corporation of the State of Ohio (the "Company"), for value received hereby promises to pay to AMBAC ASSURANCE
CORPORATION, or registered assigns, on September 1, 2037, at the office or agency of the Company in the Borough of Manhattan, The City of New York, the principal sum of
                         Dollars ($ ) in such coin or currency of the United States of America as at the time of payment
is legal tender for the payment of public and private debts, and to pay by
check to the person in whose name this Bond is registered interest thereon from the interest payment date to which interest has been paid last preceding the date hereof (unless the date hereof is an
interest payment date to which interest has been paid, in which case from the date hereof, or unless the date hereof is September 18, 2002, or prior thereto, in which case from the Initial
Interest Accrual Date (hereinbelow defined), or unless the date hereof is between a record date and the interest payment date for such record date, in which case from such interest payment date), at
the rate from time to time borne by the Ohio Air Quality Development Authority, State of Ohio, Air Quality Development Revenue Refunding Bonds, 2002 Series A (the "OAQDA Bonds") issued by the
Ohio Air Quality Development Authority ("OAQDA") under a Trust Indenture, dated as of September 1, 2002, between OAQDA and Fifth Third Bank, as trustee (the "OAQDA Indenture"), in like coin or
currency, payable at such office or agency on each Interest Payment Date (hereinbelow defined), until the Company's obligation with respect to the payment of such principal shall have been discharged;
provided, however, that in no event shall the rate of interest borne by this Bond exceed the Maximum Interest Rate (hereinbelow defined).

This
Bond is one of an issue of First Mortgage Bonds of the Company issued and to be issued in series under and pursuant to and equally secured by an indenture of mortgage and deed of
trust dated as of August 1, 1936, executed by the Company to The Bank of New York, as Trustee, as amended and supplemented as hereinafter stated, and is one of a series of such First Mortgage
Bonds, which series is designated as the First Mortgage Bonds, Series Due 2037, of the Company (the "Bonds of Series Due 2037"), the terms and provisions of which have been established by a
Thirty-ninth Supplemental Indenture dated as of September 1, 2002, executed by the Company to The Bank of New York, as Trustee. Subsequent to the execution and delivery of the indenture of
mortgage and deed of trust there have been executed and delivered thirty-nine indentures supplemental thereto, including the Thirty-

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ninth Supplemental Indenture, supplementing and amending as therein set forth certain provisions thereof. The indenture of mortgage and deed of trust and the supplemental indentures collectively are
sometimes called the Indenture.

The
"Initial Interest Accrual Date" for the Bonds of Series Due 2037 shall be the date that interest begins to accrue on the OAQDA Bonds. Each Interest Payment Date under the OAQDA
Indenture shall be an "Interest Payment Date" for the Bonds of Series 2037. The "Maximum Interest Rate" shall be the lesser of (a) 13% per annum or (b) so long as the Company is
subject to regulation by The Public Utilities Commission of Ohio ("PUCO"), 10% per annum or such other higher rate as may then be approved by the PUCO.

For
a description of the property mortgaged and pledged, the nature and extent of the security, the rights of the holders of the Bonds and of the Trustee therein and thereto, the duties
and immunities of the Trustee, and the terms and conditions upon which the Bonds are issued and secured, reference is hereby made to the Indenture. The rights and obligations of the Company and of the
holders and registered owners of the Bonds of this issue may be modified or amended at the request of the Company by an indenture or indentures supplemental to the Indenture, executed pursuant to the
consent of the holders or registered owners of at least 662/3% in principal amount of the Bonds then outstanding affected by such modification or amendment, all in the manner and
subject to the limitations set forth in the Indenture, any consent by the holder or registered owner of any Bond being conclusive and binding upon such holder or registered owner and upon all of its
future holders and owners, irrespective of whether or not any notation of such consent is made upon the Bond; provided that no such modification or amendment by such supplemental indenture shall
extend the maturity of, or reduce the rate of interest on, or otherwise modify the terms of payment of the principal of, or interest on, this Bond, which obligations are absolute and unconditional,
nor permit the creation of any lien ranking prior to or equal with the lien of the Indenture on any of the mortgaged property.

This
Bond is issued to Ambac Assurance Corporation ("Ambac") as security for the payment by the Company of its obligations under that certain Insurance Agreement dated as of
September 10, 2002 between the Company and Ambac (the "Insurance Agreement"). The Insurance Agreement was entered into in connection with the delivery by Ambac of its Financial Guaranty
Insurance Policy insuring certain payments of principal of, and interest on, the OAQDA Bonds. The proceeds of the OAQDA Bonds have been loaned to the Company pursuant to a Loan Agreement, dated as of
September 1, 2002, between OAQDA and the Company.

Notwithstanding
any other provision of this Bond, no principal shall be due and payable on this Bond unless and until an Event of Default shall have occurred under Section 4.01 of
the Insurance Agreement by reason of a failure by the Company to pay its obligations under the Insurance Agreement. If such an Event of Default under the Insurance Agreement shall occur, it shall be
deemed to be a default, for purposes of the Indenture, in the payment of an amount of principal of this Bond equal to the amount of such unpaid obligations.

If
and when interest is paid on the OAQDA Bonds for any given period of time, then there is deemed to have been paid on the Bonds of Series Due 2037 an amount of interest equal to such
interest paid on the OAQDA Bonds. The Company shall promptly notify the Trustee of the amounts and Interest Payment Dates if any interest becomes payable on this Bond.

The
Bonds of Series 2037 shall be deemed to have been paid and no longer outstanding under the Indenture to the extent that the OAQDA Bonds are paid or deemed to have been paid
and are no longer outstanding under the OAQDA Indenture and all amounts owed by the Company to Ambac under the Insurance Agreement have been indefeasibly paid in full, and the Trustee has been
notified to such effect by the Company.

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Notwithstanding
the foregoing, this Bond shall be deemed to have been paid and redeemed at any time if and to the extent that the OAQDA Bonds are redeemed pursuant to the OAQDA
Indenture, in whole or in part, in an amount equal to 100% of the principal amount of the OAQDA Bonds redeemed and all amounts owed by the Company to Ambac under the Insurance Agreement have been
indefeasibly paid in full. The Bonds of Series 2037 are not otherwise redeemable prior to their maturity.

In
the event of such redemption of the OAQDA Bonds, the Company shall notify Ambac and the Trustee that a like principal amount of this Bond shall be deemed to have been paid and
redeemed. Ambac shall surrender this Bond to the Company for cancellation and discharge by the Trustee upon the expiration of the Insurance Agreement or in the event that the Release Test (as defined
in the Insurance Agreement) is satisfied.

The
principal hereof may be declared or may become due on the conditions, in the manner and at the time set forth in the Indenture, upon the happening of a completed default as in the
Indenture provided.

This
Bond shall be transferable only as required to effect an assignment thereof to a successor-in-interest of Ambac under the Insurance Agreement. Subject to the
foregoing, this Bond is transferable as prescribed in the Indenture by the registered owner hereof in person, or by his duly authorized attorney, at the office or agency of the Company in the Borough
of Manhattan, The City of New York, upon surrender and cancellation of this Bond; and thereupon a new registered Bond or Bonds of Series Due 2037 for a like principal amount and of authorized
denominations will be issued to the transferee in exchange therefor as provided in the Indenture, and upon payment, if the Company shall require it, of the charges therein prescribed. The Company and
the Trustee may deem and treat the person in whose name this Bond is registered as the absolute owner hereof for the purpose of receiving payment of or on account of the principal and interest due
hereon and for all other purposes.

Bonds
of Series Due 2037 are issuable as registered Bonds in the denominations of $1,000 and integral multiples thereof.

No
recourse shall be had for the payment of the principal of, or interest on, this Bond, or under or upon any obligation, covenant, or agreement contained in the Indenture, against any
incorporator or any past, present, or future subscriber to capital stock, shareholder, officer, or director, as such, of the Company or of any predecessor or successor corporation, either directly or
through the Company or any predecessor or successor corporation, under any present or future rule of law, statute, or constitution or by the enforcement of any assessment or otherwise, all such
liability of incorporators, subscribers, shareholders, officers, and directors being released by the registered owner hereof by the acceptance of this Bond and being likewise waived and released by
the terms of the Indenture.

This
Bond shall not become valid or obligatory for any purpose until The Bank of New York, the Trustee under the Indenture, or its successor thereunder, shall have signed the form of
certificate endorsed hereon.

IN
WITNESS WHEREOF, The Cincinnati Gas & Electric Company has caused this Bond to be signed in its name by its President or a Vice President, manually or in facsimile, and its
corporate seal or a facsimile thereof to be affixed hereto or reproduced hereon and attested by its Secretary or an Assistant Secretary, manually or in facsimile.

Dated

| |  | THE CINCINNATI GAS & ELECTRIC COMPANY,
| |  | --------------------------------------
| |  | By                                    
| |  |                                       

|Attest: |  |           |  | 
|------- |  | --------- |  | 
|        |  | Secretary |  | 

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[FORM OF TRUSTEE'S CERTIFICATE ON ALL BONDS OF SERIES DUE 2037]

This
Bond is one of the Bonds, of the series designated therein, described in the within-mentioned Indenture.

| |  | THE BANK OF NEW YORK,
                                         
       Trustee,
| |  | -------------------------------------------------------------------------------
| |  |                                                                                
| |  | By                                                                             
| |  |                                                                                

[THE REMAINDER OF THIS PAGE HAS BEEN LEFT BLANK INTENTIONALLY.]

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WHEREAS,
all things necessary to make the Bonds of Series Due 2037 herein described, when duly authenticated by the Trustee and issued by the Company, valid, binding, and legal
obligations of the Company, and to make this Thirty-ninth Supplemental Indenture a valid and binding agreement supplemental to the First Mortgage, have been done and performed;

THIS
THIRTY-NINTH SUPPLEMENTAL INDENTURE WITNESSETH

In
consideration of the premises and of the acceptance and purchase of the Bonds of Series Due 2037, the Company agrees with the Trustee as follows:

ARTICLE ONE
BONDS OF SERIES DUE 2037 AND ISSUE THEREOF

SECTION 1.    There shall be a series of Bonds designated as set forth in the second paragraph of the form of Bond, each of which shall bear the
descriptive title First Mortgage Bond. The aggregate principal amount of the Bonds of Series Due 2037 which may be outstanding under the First Mortgage as amended and this Thirty-ninth Supplemental
Indenture shall be limited to $84,000,000, except as provided in Section 9 of Article Two of the First Mortgage as amended.

The
Bonds of Series Due 2037 and the Trustee's certificate to be endorsed on all the Bonds of such series shall respectively be substantially as recited above, with such appropriate
omissions, insertions, and variations as in the First Mortgage as amended and in this Thirty-ninth Supplemental Indenture permitted.

SECTION 2.    Upon
the execution and delivery of this Thirty-ninth Supplemental Indenture and upon delivery to the Trustee of $84,000,000 aggregate principal amount of
Bonds of Series Due 2037, executed by the Company, and upon compliance by the Company with the provisions of the First Mortgage as amended, the Trustee shall, without awaiting the filing or recording
of this Thirty-ninth Supplemental Indenture, authenticate and deliver the Bonds.

SECTION 3.    Bonds
of Series Due 2037 shall be dated the date of their authentication, shall mature on September 1, 2037, shall bear interest at the rate set
forth in the first paragraph of the form of Bond until paid or redeemed as hereinafter provided, payable by check on each Interest Payment Date (as defined the form of the Bond), and shall be payable
as to both principal and interest in such coin or currency of the United States of America as at the time of payment is legal tender for the payment of public and private debts, at the office or
agency of the Company in The City of New York.

SECTION 4.    The
Bonds of Series 2037 shall be issued in the form of a separate, single, authenticated, fully registered bond for each such series which need not
be in the form of a lithographed or engraved certificate, but may be typewritten or printed on ordinary paper or such paper as the Trustee may reasonably request and shall be registered in the name of
Ambac Assurance Corporation ("Ambac").

The
Bonds of Series 2037 are being issued to Ambac as security for the payment by the Company of its obligations under the Insurance Agreement, dated as of September 1,
2002, between Ambac and the Company (the "Insurance Agreement"), which was entered into in connection with the delivery by Ambac of its Financial Guaranty Insurance Policy insuring certain payments of
principal of, and interest on, certain bonds (the "OAQDA Bonds") to be issued under a Trust Indenture, dated as of September 1, 2002, between the Ohio Air Quality Development Authority
("OAQDA") and Fifth Third Bank, as trustee (the "OAQDA Indenture"). The proceeds of the OAQDA Bonds will be loaned to the Company pursuant to a Loan Agreement, dated as of September 1, 2002,
between the OAQDA and the Company.

The
Bonds of Series 2037 shall be transferable only as required to effect an assignment thereof to a successor-in-interest of Ambac under the Insurance
Agreement.

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Bonds
of Series Due 2037 shall be issued in the denominations of $1,000 and authorized multiples thereof.

SECTION 5.    If
and when interest is paid on the OAQDA Bonds for any given period of time, then there is deemed to have been paid on the Bonds of Series 2037 an
amount of interest equal to such interest paid on the OAQDA Bonds. The Company shall promptly notify the Trustee of the amounts and Interest Payment Dates if any interest becomes payable on the Bonds
of Series 2037.

For
purposes of the calculation required by Section 5 of Article Five of the First Mortgage as amended, annual interest in respect of: the Bonds of Series 2037 shall be
equal to the sum of (i) the sum of the amounts determined by multiplying the principal amount of the OAQDA Bonds, if any, outstanding on the date of such calculation which bear a fixed rate of
interestbysuch fixed rate, plus (ii) the amount determined by multiplying the aggregate principal amount of the OAQDA Bonds, if any,
outstanding on the date of such calculation which bear interest at rates which may fluctuate or may fluctuate from time to time in accordance with methods specified in such OAQDA Bonds by13% per annum.

SECTION 6.    The
Bonds of Series 2037 shall be deemed to have been paid and redeemed at any time if and to the extent that the OAQDA Bonds are redeemed pursuant
to the OAQDA Indenture relating thereto, in whole or in part, in an amount equal to 100% of the principal amount of the OAQDA Bonds redeemed and all amounts owed by the Company to Ambac under the
Insurance Agreement have been indefeasibly paid in full. In the event of such redemption of the OAQDA Bonds, the Company shall notify Ambac and the Trustee that a like principal amount of the Bonds of
Series 2037 shall be deemed to have been paid and redeemed. The Bonds of Series 2037 are not otherwise redeemable prior to their maturity.

SECTION 7.    The
covenant to provide a Maintenance and Replacement Fund contained in the provisions of Section 5 of Article Eight of the First Mortgage as
amended shall not apply in respect of the Bonds of Series Due 2037.

ARTICLE TWO
COVENANTS OF THE COMPANY

SECTION 1.    All covenants and agreements by the Company in the First Mortgage as heretofore and hereby amended are hereby confirmed, except the
covenant contained in Section 5 of Article Eight.

SECTION 2.    So
long as any Bonds of Series Due 2037 shall be outstanding the Company(a)will not sell or otherwise
dispose of any equity securities owned by it of The Union Light, Heat and Power Company, a Kentucky corporation (the "Subsidiary") otherwise than to the Subsidiary or otherwise than as part of a
merger or consolidation of the Subsidiary into or with the Company or the liquidation of the Subsidiary, unless all the equity securities owned by the Company of the Subsidiary shall be sold or
otherwise disposed of and the proceeds of such sale or other disposition deposited with the Trustee hereunder to be held and disposed of as provided in Section 5 of Article Eleven of the First
Mortgage as amended, and(b)will not permit the Subsidiary to sell, otherwise than to the Company, any equity
securities issued by the Subsidiary; provided that nothing in this clause(b)shall prevent the Subsidiary, in connection with the sale of equity
securities to the Company, from selling equity securities to others than the Company to the extent necessary to satisfy the preemptive rights of minority stockholders under applicable law.

So
long as any Bonds of Series Due 2037 shall be outstanding, the Company(a)will not sell or otherwise dispose of any securities, other
than equity securities, owned by it of the Subsidiary otherwise than to the Subsidiary or otherwise than as part of the merger or consolidation of the Subsidiary into or with the Company; or (b)so long
as any equity securities of the Subsidiary shall be owned by the

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Company, will not permit the Subsidiary to issue or sell, otherwise than to the Company, any securities, other than equity securities, issued by the Subsidiary if, in either case, after giving effect
to such sale or other disposition, the outstanding securities, other than equity securities, of the Subsidiary will be in excess of 75% of the plant account of the Subsidiary as shown by its books as
of the end of the calendar month next preceding such sale or other disposition after deducting from such plant account the amount of the reserves for depreciation and amortization applicable thereto
shown by the books of the Subsidiary and any other reserves shown by its books which are applicable to such plant account or any part thereof.

The
term "equity securities", as used in this Section, shall mean any securities other than bonds, notes, or other evidences of indebtedness bearing interest at a fixed rate and payable
on demand or having a fixed maturity date.

ARTICLE THREE
AMENDMENT OF ARTICLE ONE, ARTICLE FIVE, ARTICLE ELEVEN, AND
ARTICLE EIGHTEEN OF THE FIRST MORTGAGE AS AMENDED

SECTION 1.  The Bonds of Series Due 2037 are hereby excluded from subdivision (7) of Section 5 of Article One of the First
Mortgage as heretofore and hereby amended or supplemented.

SECTION 2.  Article
Eleven of the First Mortgage is hereby amended by inserting after the words "or other similar property," in subdivision (1) of
Section 2 thereof the following:



SECTION 3.  Article
Five of the First Mortgage is hereby amended by substituting for the words "in a principal amount not exceeding sixty per centum (60%) of" in
Section 3 thereof the following:



SECTION 4.  Article
Eighteen of the First Mortgage is hereby amended by:



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ARTICLE FOUR
MISCELLANEOUS

SECTION 1.  The provisions of this Thirty-ninth Supplemental Indenture shall become effective immediately upon the execution and delivery
hereof, except that the provisions hereof modifying and amending the First Mortgage as amended shall become effective simultaneously with and upon the
initial issue of Bonds of Series Due 2037. From and after such initial issue of Bonds of Series Due 2037, this Thirty-ninth Supplemental Indenture shall form a part of the First Mortgage and
all the terms and conditions hereof shall be deemed to be part of the terms of the First Mortgage, as fully and with the same effect as if they had been set forth in the First Mortgage as originally
executed. Except as modified or amended by this Thirty-ninth Supplemental Indenture, the First Mortgage as amended shall remain and continue in full force and effect in accordance with the terms and
provisions thereof, and all the covenants, conditions, terms, and provisions of the First Mortgage as amended shall be applicable with respect to the Bonds of Series Due 2037, except in so far as such
covenants, conditions, terms, and provisions are limited and applicable only to the Bonds of another or other series, and all the covenants, conditions, terms, and provisions of the First Mortgage as
amended with respect to the Trustee shall remain in full force and effect and be applicable to the Trustee under this Thirty-ninth Supplemental Indenture in the same manner as though set out herein at
length. All representations and recitals contained in this Thirty-ninth Supplemental Indenture and in the Bonds of Series Due 2037 (save only the Trustee's certificate upon such Bonds) are made by and
on behalf of the Company, and the Trustee is in no way responsible therefor or for any statement therein contained or for the validity or sufficiency thereof.

SECTION 2.  The
terms defined in Article One of the First Mortgage as heretofore and hereby amended, when used in this Thirty-ninth Supplemental Indenture shall,
respectively, have the meanings set forth in such Article.

No
Bonds of Series Due 2037 shall be deemed to be outstanding within the meaning of the phrase "so long as any of the Bonds of Series Due 2037 shall be outstanding" as used in this
Thirty-ninth Supplemental Indenture, if the Company shall have redeemed all the Bonds of Series Due 2037 in accordance with this Thirty-ninth Supplemental Indenture.

SECTION 3.  This
Thirty-ninth Supplemental Indenture may be executed in several counterparts and each counterpart shall be an original instrument.

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IN
WITNESS WHEREOF, THE CINCINNATI GAS & ELECTRIC COMPANY has caused this instrument to be signed on its behalf by one of its Vice Presidents and its corporate seal to be hereunto
affixed and attested by its Secretary, and The Bank of New York has caused this instrument to be signed on its behalf by a Vice President and its corporate seal to be hereunto affixed and attested by
an Assistant Treasurer, as of the day and year first above written.

|                                                                                            |  | THE CINCINNATI GAS & ELECTRIC COMPANY,
|------------------------------------------------------------------------------------------- |  | --------------------------------------
|                                                                                            |  | By                                    
|ATTEST:                                                                                     |  |                                       
|/s/JEROME A. VENNEMANNJerome A. Vennemann,Secretary                                         |  | (CORPORATE SEAL)                      
|Signed and acknowledged in our presence on behalf of
THE CINCINNATI GAS & ELECTRIC COMPANY: |  |                                       
|/s/DEBBY GARRETTDebby Garrett,Witness                                                       |  |                                       
|/s/JULIE M. THOMPSONJulie M. Thompson,Witness                                               |  |                                       
|                                                                                            |  | THE BANK OF NEW YORK,                 
|                                                                                            |  | By                                    
|ATTEST:                                                                                     |  |                                       
|/s/JOSEPH LLORETJoseph Lloret,Assistant Treasurer                                           |  | (CORPORATE SEAL)                      
|Signed and acknowledged in our presence on behalf of
THE BANK OF NEW YORK:                  |  |                                       
|/s/MARY LAGUMINAMary LaGumina,Witness                                                       |  |                                       
|/s/PATRICIA GALLAGHERPatricia Gallagher,Witness                                             |  |                                       

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|STATE OF OHIO      |  | ) |     | 
|------------------ |  | - | --- | 
|                   |  | ) | SS: | 
|COUNTY OF HAMILTON |  | ) |     | 

On this 9th day of September 2002,RONALD R. REISINGandJEROME A.
VENNEMANN, came before me and acknowledged that they signed and sealed this instrument asVICE PRESIDENTFINANCEand SECRETARY, respectively, ofTHE CINCINNATI GAS & ELECTRIC COMPANYand that the same were free
acts; and suchVICE PRESIDENTFINANCE, being duly sworn, said that he resides inHAMILTON COUNTY,
OHIO, that he is aVICE PRESIDENTof the corporation, that the seal affixed hereto is its corporate seal, that it was affixed by
order of its Board of Directors, and that he signed his name thereto by like order.

IN
WITNESS WHEREOF I have signed my name and affixed my official seal.

|(NOTARIAL SEAL)                  |  |                     
|-------------------------------- |  | --------------------
|                                 |  |                     
|                                 |  | /s/CECILIA A. TEMPLE
|                                 |  | Notary Public       
|My commission expires 09-28-03.  |  |                     
|County of residence:    Hamilton |  |                     

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|STATE OF NEW YORK  |  | ) |     | 
|------------------ |  | - | --- | 
|                   |  | ) | SS: | 
|COUNTY OF NEW YORK |  | ) |     | 

On this 10th day of September 2002,PAUL SCHMALZELandJOSEPH
LLORET, came before me and acknowledged that they signed and sealed this instrument asVICE PRESIDENTand ASSISTANT TREASURER, respectively, ofTHE BANK OF NEW YORK, and that the same were free acts; and such VICE PRESIDENTbeing duly sworn, said that he resides inEATONTOWN, NEW
JERSEY, that he is a VICE PRESIDENTofTHE BANK OF NEW YORK, that the seal affixed hereto is its corporate seal, that it was
affixed by authority of its Board of Directors, and that he signed his name thereto by like authority.

IN
WITNESS WHEREOF I have signed my name and affixed my official seal.

|                              |  | (NOTARIAL SEAL) 
|----------------------------- |  | ----------------
|                              |  | /s/ROBERT HIRSCH
|                              |  | Notary Public   
|My commission expires 2006.   |  |                 
|County of residence: New York |  |                 

This instrument was prepared by:

Bradley
C. Arnett, Esq.
139 East Fourth Street
Cincinnati, Ohio 45202

-12-

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