<PAGE>                              
                        
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              THE DAYTON POWER AND LIGHT COMPANY
                              
                            AND
                        
                    THE BANK OF NEW YORK
               (formerly Irving Trust Company)
                          Trustee
                              
                        
                              
                       --------------

             Forty-First Supplemental Indenture

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                Dated as of February 1, 1999
                              
                              
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<PAGE>
             THE DAYTON POWER AND LIGHT COMPANY
                              
             Forty-First Supplemental Indenture
                Dated as of February 1, 1999
                              
                         -----------

                      TABLE OF CONTENTS
                              
                              
                                                                 Page
                                                                 ----

Parties                                                           1

Recitals                                                          1


                        ARTICLE ONE.
                              
           Amendment to First Mortgage as Amended.
                              
Amendment to First Mortgage as Amended                            4 

                              
                        ARTICLE TWO.
                              
                       Miscellaneous.

Sec. 1    Forty-First Supplemental Indenture to Form Part of
          First Mortgage.                                         4    

Sec. 2    Definitions in First Mortgage Shall Apply to
          Forty-First Supplemental Indenture                      4

Sec. 3    Execution in Counterparts                               5

Testimonium                                                       5

Signatures                                                        5

Acknowledgments                                                   6


       
                              
                             -1-  
                              
<PAGE>                              
     FORTY-FIRST SUPPLEMENTAL INDENTURE, dated as of
February 1, 1999 between The Dayton Power and Light Company,
a corporation of the State of Ohio (hereinafter sometimes
called the Company), party of the first part, and The Bank
of New York (formerly Irving Trust Company), a corporation
of the State of New York, as Trustee (hereinafter sometimes
called the Trustee), party of the second part.

     Whereas, the Company has heretofore executed and
delivered to Irving Trust Company (now The Bank of New York)
a certain Indenture, dated as of October 1, 1935 (hereinafter
sometimes called 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 (hereinafter
sometimes called the Bonds); and

     Whereas, the Company has heretofore executed and
delivered to the Trustee forty supplemental indentures
numbered, dated and providing for their respective series of
First Mortgage Bonds, all as set forth in the tabulation
below (the First Mortgage as amended and supplemented by the
First through the Fortieth Supplemental Indentures is
hereinafter called the First Mortgage as amended):
     
                                              
                                                           Principal
Supplemental                           Series               Amount
 Indenture       Dated As Of         Provided For         Outstanding
------------     ------------        ------------         -----------
First            March 1, 1937        3.25% Series            None
                                       Due 1962      
Second           January 1, 1940      3% Series               None
                                       Due 1970      
Third            October 1, 1945      2.75% Series            None
                                       Due 1975      
Fourth           January 1, 1948      3% Series               None
                                       Due 1978      
Fifth            December 1, 1948     3% Series A             None
                                       Due 1978      
Sixth            February 1, 1952     3.25% Series            None
                                       Due 1982      
Seventh          September 1, 1954    3% Series               None
                                       Due 1984      
Eighth           November 1, 1957     5% Series               None
                                       Due 1987      
Ninth            March 1, 1960        5.125% Series           None
                                       Due 1990      
Tenth            June 1, 1963         4.45% Series            None
                                       Due 1993      
Eleventh         May 1, 1967          5.625% Series           None
                                       Due 1997      
Twelfth          June 15, 1968        6.75% Series            None
                                       Due 1998

                             -2-

<PAGE>
                                                           Principal
Supplemental                           Series               Amount
 Indenture       Dated As Of         Provided For         Outstanding
------------     -----------         ------------         -----------
Thirteenth       October 1, 1969      8.25% Series            None
                                       Due 1999      
Fourteenth       June 1, 1970         9.5% Series             None
                                       Due 2000      
Fifteenth        August 1, 1971       8.125% Series           None
                                       Due 2001           
Seventeenth      November 1, 1973     8% Series               None
                                       Due 2003      
Eighteenth       October 1, 1974      10.125% Series          None
                                       Due 1981      
Nineteenth       August 1, 1975       10.70% Series           None
                                       Due 2005      
Twentieth        November 15, 1976    8.75% Series            None
                                       Due 2006      
Twenty-First     April 15, 1977       6.35% Series        $11,800,000
                                       Due 2007      
Twenty-Second    October 15, 1977     8.5% Series             None
                                       Due 2007      
Twenty-Third     April 1, 1978        8.95% Series            None
                                       Due 1998      
Twenty-Fourth    November 1, 1978     9.5% Series             None
                                       Due 2003      
Twenty-Fifth     August 1, 1979       10.25% Series           None
                                       Due 1999      
Twenty-Sixth     December 1, 1979     12.125% Series          None
                                       Due 2009      
Twenty-Seventh   February 1, 1981     14.625% Series          None
                                       Due 1988      
Twenty-Eighth    February 18, 1981    14.5% Series            None
                                       Due 1988      
Twenty-Ninth     September 1, 1981    17% Series              None
                                       Due 1991      
Thirtieth        March 1, 1982        16.75% Series           None
                                       Due 2012      
Thirty-First     November 1, 1982     11.5% Series            None
                                       Due 2012-A    
Thirty-Second    November 1, 1982     11.5% Series            None
                                       Due 2012-B    
                              
                              
                              
                             -3-

<PAGE>
                                                           Principal
Supplemental                           Series               Amount
 Indenture       Dated As Of         Provided For         Outstanding
------------     -----------         ------------         ----------- 
Thirty-Third     December 1, 1985     9.5% Series             None
                                       Due 2015      
Thirty-Fourth    April 1, 1986        9% Series               None
                                       Due 2016      
Thirty-Fifth     December 1, 1986     8.875% Series           None
                                       Due 2016        
Thirty-Sixth     August 15, 1992      6.40% Pollution     $32,300,000
                                       Control Series
                                       1992-A Due 2027   
                                      6.40% Pollution     $27,800,000
                                       Control Series
                                       1992-B Due 2027
Thirty-Seventh   November 15, 1992    6.50% Pollution     $48,000,000
                                       Control Series
                                       1992-C Due 2022   
Thirty-Eighth    November 15, 1992    8.40% Series       $225,000,000
                                       Due 2022      
Thirty-Ninth     January 15, 1993     8.15% Series       $226,000,000
                                       Due 2026      
Fortieth         February 15, 1993    7.875% Series      $220,000,000
                                       Due 2024      
                              
     Whereas, the Company, by resolutions duly adopted by
its Board of Directors, has determined to make a certain
amendment hereinafter set forth in the terms and provisions
of the First Mortgage as amended; and
                              
     Whereas, 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 curing any ambiguity
or of curing or correcting any defective provisions, contained
in the First Mortgage or in any supplemental indenture; and
                              
     Whereas, the Company has requested the Trustee, pursuant 
to Section 1 of Article Eighteen of the First Mortgage as
amended, to enter into this Forty-First Supplemental Indenture
for the purpose of curing an ambiguity or of curing or correcting
a defective provision in Section 3 of Article Eleven of the First
Mortgage as amended; and
                              
                             -4-

<PAGE>
     Whereas, by said resolutions the Board of Directors of
the Company duly approved the form, terms and provisions of
this Forty-First Supplemental Indenture and duly authorized
and directed the execution by the Company of an indenture in the
form and having the terms and the provisions so approved; and

     Whereas, all things necessary to make this Indenture a
valid and binding agreement supplemental to the First Mortgage,
have been done and performed.

                         ARTICLE ONE.

              Amendment of the First Mortgage.

     That part of the first paragraph of Section 3 of
Article Eleven of the First Mortgage as amended which
precedes subdivision (1) of said Section is hereby restated
so as to read as follows:

     "So long as the Company is not in default under
     any of the provisions of this Indenture, the
     Company may obtain the release of any of the
     mortgaged and pledged property, including, without
     limiting the generality of the foregoing, any one
     or more of the Company's heating, gas or water
     properties substantially as an entirety (provided,
     however, that the electric property of the Company
     shall not in any event be released substantially
     as an entirety and, further, that prior lien bonds
     deposited with the Trustee shall not be released
     except as provided in Article Nine hereof), and
     the Trustee shall release the same from the lien
     hereof upon the application of the Company and
     receipt by the Trustee of"

                        ARTICLE TWO.

                       Miscellaneous.

     SECTION 1.  The provisions of this Forty-First
Supplemental Indenture shall become effective immediately
upon the execution and delivery hereof.  From and after such
time, this Forty-First Supplemental Indenture shall form a
part of the First Mortgage as amended and all the terms and
conditions hereof shall be deemed to be part of the terms of
the First Mortgage as amended, 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 Forty-First 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 with respect to the Trustee
shall remain in full force and effect and be applicable to
the Trustee under this Forty-First Supplemental Indenture in
the same manner as though set out herein at length.  All
representations and recitals contained in this Forty-First
Supplemental Indenture are made by and on behalf of the
Company, and the Trustee is in no way responsible therefor
or for any statement therein contained.

                             -5-

<PAGE>
     SECTION 2.  The terms defined in Article One of the
First Mortgage as amended, when used in this Forty-First
Supplemental Indenture, shall, respectively, have the
meanings set forth in such Article.

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

     In Witness Whereof, The Dayton Power and Light Company
has caused this instrument to be signed on its behalf by its
President or a Vice President and its corporate seal to be
hereunto affixed and attested by its Secretary or an
Assistant Secretary, in the City of Dayton, Ohio, and The
Bank of New York has caused this instrument to be signed on
its behalf by a Vice President or an Assistant Vice
President and its corporate seal to be hereunto affixed and
attested by an Assistant Treasurer, in The City of New York,
New York, as of the day and year first above written.


                    The Dayton Power and Light Company

[SEAL]              By: /s/James P. Torgerson
                    ----------------------------------

Attest:

/s/Stephen F. Koziar Jr.
------------------------


Signed and acknowledged in our presence by
The Dayton Power and Light Company.

Name: /s/Michael D. Lopez
-------------------------

Name: /s/Timothy G. Rice
------------------------









                             -6-

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                              The Bank of New York

[SEAL]                        By: /s/Michael Culhane
                              ----------------------

Attest:

/s/Mary Beth Lewicki
--------------------


Signed and acknowledged in our presence by
The Bank of New York.


Name: /s/Patrick O'Leary
------------------------


Name: /s/Anthony M. Hitchman
----------------------------























                             -7-

<PAGE>
State of Ohio,        ) ss.:
County of Montgomery, )


     On this first day of February, 1999, personally
appeared before me, a Notary Public within and for said
County in the State aforesaid, James P. Torgerson, and
Stephen F. Koziar, to me known and known to me to be,
respectively, a Vice President, CFO and Treasurer and the
Group Vice President and Secretary of The Dayton Power and
Light Company, one of the corporations which executed the
foregoing instrument, who severally acknowledged that they
did sign and seal said instrument as such Vice President,
CFO and Treasurer and Group Vice President and Secretary for
and on behalf of said corporation and that the same is their
free act and deed as such Vice President, CFO and Treasurer
and Group Vice President and Secretary , respectively, and
the free and corporate act and deed of said corporation; and
said Stephen F. Koziar, being by me duly sworn, did depose
and say:  that he resides in Montgomery County; that he is a
Group Vice President and Secretary of The Dayton Power and
Light Company, one of the corporations described in and
which executed the above instrument; that he knows the seal
of said corporation; that the seal affixed to said instrument
is such corporate seal; that it was so affixed by order of
the Board of Directors of said corporation; and that he
signed his name thereto by like order.


     In Witness Whereof I have hereunto set my hand and
official seal.

[SEAL]
                              /s/Timothy G. Rice
                              ------------------


State of New York,  ) ss.:
County of New York, )

     On this second day of February, 1999, personally appeared
before me, a Notary Public within and for said County in the
State aforesaid, Michael Culhane and Mary Beth Lewicki, to me
known and known to me to be, respectively, a Vice President
and an Assistant Vice President of The Bank of New York, one
of the corporations which executed the foregoing instrument,
who severally acknowledged that they did sign and seal said
instrument as such Vice President and Assistant Vice
President for and on behalf of said corporation and that the
same is their free act and deed as such Vice President and
Assistant Vice President, respectively, and the free and
corporate act and deed of said corporation; and said Michael
Culhane being by me duly sworn, did depose and say:  that he
resides in Brooklyn, New York; that he is a Vice President,
of The Bank of New York, one of the corporations described...
                              
                              
                              

                             -8-

<PAGE>
 ...in and which executed the above instrument; that he knows
the seal of said corporation; that the seal affixed to said
instrument is such corporate seal; that it was so affixed by
order of the Board of Directors of such corporation; and
that he signed his name thereto by like order.
                              
     In Witness Whereof I have hereunto set my hand and
official seal.
     
     [SEAL]
                              /s/William J. Cassels
                              ---------------------
     
     
                              This instrument prepared by
                              
                              
                              /s/Timothy G. Rice
                              ----------------------------------
                              Senior Counsel
                              The Dayton Power and Light Company
                              1065 Woodman Drive
                              Dayton, Ohio  45432
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
     
                             -9-