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                         POTOMAC ELECTRIC POWER COMPANY
 
                1900 PENNSYLVANIA AVENUE, N.W., WASHINGTON, D.C.
 
                                       TO
 
                            THE RIGGS NATIONAL BANK
                              OF WASHINGTON, D.C.
 
                    800-17TH STREET, N.W., WASHINGTON, D.C.
                                                                      AS TRUSTEE
 
                              ------------------
 
                             Supplemental Indenture
 
                             DATED AS OF     , 1995
 
                              ------------------
 
                   SUPPLEMENTAL TO MORTGAGE AND DEED OF TRUST
 
                               DATED JULY 1, 1936
 
                              ------------------
 
                   FIRST MORTGAGE BONDS,   % SERIES DUE
 
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                        POTOMAC ELECTRIC POWER COMPANY
 
                SUPPLEMENTAL INDENTURE DATED AS OF      , 1995
 
                              TABLE OF CONTENTS*
 
                              ------------------
 


                                                                           PAGE
                                                                     
 Parties..................................................................   1
 Recitals.................................................................   1
 
                                    PART I
 
                             Description of Bonds
 
 Section 1. General description of Bonds of    Series....................    6
 Section 2. Form of face of Bond of    Series............................    7
            Form of Trustee's certificate................................    9
            Text appearing on reverse side of Bond of    Series..........   10
 Section 3. Denominations of Bonds of    Series..........................   13
 Section 4. Execution and form of temporary Bonds........................   13
 
                                    PART II
 
                                Issue of Bonds
 
 Section 1. Limitation as to principal amount............................   13
 Section 2. Issue of Bonds...............................................   14
 
                                   PART III
 
                                  Redemption
 
 Section 1. Bonds of    Series redeemable ...............................   14
 Section 2. Notice of Redemption, etc. ..................................   15
 
                                    PART IV
 
                Additional Particular Covenants of the Company

 Section 1. Company not to withdraw moneys pursuant to Section 2 of
             Article VIII in excess of an amount equal to principal
             amount of issued refundable bonds...........................   15
 Section 2. No property additions made on or prior to December 31, 1946
             to be used for any purpose under the Indenture..............   15

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  * The Table of Contents is not part of the Supplemental Indenture and should
not be considered as such. It is included herein only for purposes of
convenient reference.

 
                                     PART V
 


                                                                           PAGE
                                                                        
Amendment of Indenture to Permit Qualification Under Trust Indenture Act
  of 1939.................................................................  16
 
                                    PART VI
 
Amendment of Original Indenture...........................................  16
 
                                    PART VII
 
                                  The Trustee
 
Acceptance of trusts by the Trustee.......................................  16
Trustee not responsible for validity of the Supplemental Indenture........  17
 
                                   PART VIII
 
                            Miscellaneous Provisions
 
Execution of Supplemental Indenture in counterparts.......................  17
Appointment of attorneys-in-fact by parties...............................  17
Testimonium...............................................................  17
Execution.................................................................  18
Company's Acknowledgments.................................................  19
Trustee's Acknowledgments.................................................  21

 
                                       ii

 
 SUPPLEMENTAL INDENTURE, dated as of the    day of    , nineteen hundred and
ninety-five (1995), made by and between Potomac Electric Power Company, a cor-
poration organized and existing under the laws of the District of Columbia and
a domestic corporation of the Commonwealth of Virginia (hereinafter sometimes
called the "Company"), party of the first part, and The Riggs National Bank of
Washington, D.C., a national banking association organized and existing under
the laws of the United States of America (hereinafter sometimes called the
"Trustee"), as Trustee under the Mortgage and Deed of Trust dated July 1,
1936, hereinafter mentioned, party of the second part;
 
 Whereas, The Company has heretofore executed and delivered its Mortgage and
Deed of Trust, dated July 1, 1936 (hereinafter sometimes referred to as the
"Original Indenture"), to the Trustee, to secure an issue of First Mortgage
Bonds of the Company, issuable in series; and
 
 Whereas, pursuant to the terms and provisions of the Original Indenture, in-
dentures supplemental thereto dated as of July 1, 1936, December 1, 1939, Au-
gust 1, 1940, August 1, 1942, January 1, 1948, May 1, 1949, May 1, 1950, March
1, 1952, May 15, 1953, May 16, 1955, June 1, 1956, December 1, 1958, November
16, 1959, December 1, 1960, February 15, 1963, May 15, 1964, April 1, 1966,
May 1, 1967, February 15, 1968, March 15, 1969, February 15, 1970, August 15,
1970, September 15, 1972, April 1, 1973, January 2, 1974, August 15, 1974, Au-
gust 15, 1974, June 15, 1977, July 1, 1979, June 16, 1981, June 17, 1981, De-
cember 1, 1981, August 1, 1982, October 1, 1982, April 15, 1983, November 1,
1985, March 1, 1986, November 1, 1986, March 1, 1987, September 16, 1987, May
1, 1989, August 1, 1989, April 5, 1990, May 21, 1991, May 7, 1992, September
1, 1992, November 1, 1992, March 1, 1993, March 2, 1993, July 1, 1993, August
20, 1993, September 29, 1993, September 30, 1993, October 1, 1993, February
10, 1994, February 11, 1994 and March 10, 1995 have been heretofore entered
into between the Company and the Trustee to provide, respectively, for the
creation of the first through the fifty-ninth series of Bonds thereunder and,
in the case of the supplemental indentures dated January 1, 1948, March 1,
1952, May 15, 1953, May 16, 1955, June 1, 1956, September 15, 1972, July 1,
1979, June 17, 1981, November 1, 1985, September 16, 1987, May 1, 1989, May
21, 1991, May 7, 1992, July 1, 1993 and one of the supplemental indentures
dated August 15, 1974, to convey additional property; and

 
 Whereas, $20,000,000 principal amount of Bonds of the 3 1/4% Series due 1966
(the first series), $5,000,000 principal amount of Bonds of the 3 1/4% Series
due 1974 (the second series), $10,000,000 principal amount of Bonds of the 3
1/4% Series due 1975 (the third series), $5,000,000 principal amount of Bonds
of the 3 1/4% Series due 1977 (the fourth series), $15,000,000 principal amount
of Bonds of the 3% Series due 1983 (the fifth series), $10,000,000 principal
amount of Bonds of the 2 7/8% Series due 1984 (the sixth series), $30,000,000
principal amount of Bonds of the 2 3/4% Series due 1985 (the seventh series),
$15,000,000 principal amount of Bonds of the 3 1/4% Series due 1987 (the eighth
series), $10,000,000 principal amount of Bonds of the 3 7/8% Series due 1988
(the ninth series), $10,000,000 principal amount of Bonds of the 3 3/8% Series
due 1990 (the tenth series), $10,000,000 principal amount of Bonds of the 3
5/8% Series due 1991 (the eleventh series), $25,000,000 principal amount of
Bonds of the 4 5/8% Series due 1993 (the twelfth series), $15,000,000 principal
amount of Bonds of the 5 1/4% Series due 1994 (the thirteenth series),
$45,000,000 principal amount of Bonds of the 7 3/4% Series due 2004 (the twen-
tieth series), $35,000,000 principal amount of Bonds of the 8.85% Series due
2005 (the twenty-first series), $70,000,000 principal amount of Bonds of the 9
1/2% Series due August 15, 2005 (the twenty-second series), $50,000,000 princi-
pal amount of Bonds of the 7 3/4% Series due 2007 (the twenty-third series),
$25,000,000 principal amount of Bonds of the 5 5/8% Series due 1997 (the twen-
ty-fourth series), $100,000,000 principal amount of Bonds of the 8 3/8% Series
due 2009 (the twenty-fifth series), $50,000,000 principal amount of Bonds of
the 10 1/4% Series due 1981 (the twenty-sixth series), $50,000,000 principal
amount of Bonds of the 10 3/4% Series due 2004 (the twenty-seventh series),
$38,300,000 principal amount of Bonds of the 6 1/8% Series due 2007 (the twen-
ty-eighth series), $15,000,000 principal amount of Bonds of the 6 1/2% Series
due 2004 (the twenty-ninth series), $20,000,000 principal amount of Bonds of
the 6 1/2% Series due 2007 (the thirtieth series), $7,500,000 principal amount
of Bonds of the 6 5/8% Series due 2009 (the thirty-first series), $30,000,000
principal amount of Bonds of the Floating Rate Series due 2010 (the thirty-sec-
ond series), $50,000,000 principal amount of Bonds of the 14 1/2% Series due
1991 (the thirty-third series), $60,000,000 principal amount of Bonds of the 14
1/4% Series due 1992 (the thirty-fifth series), $50,000,000 principal amount of
Bonds of the 11 7/8% Series due 1989 (the thirty-sixth series), $37,000,000
 
                                       2

 
principal amount of Bonds of the 8 3/4% Series due 2010 (the thirty-seventh se-
ries), $75,000,000 principal amount of Bonds of the 11 1/4% Series due 2015
(the thirty-eighth series), $75,000,000 principal amount of Bonds of the 9 1/4%
Series due 2016 (the thirty-ninth series), $75,000,000 principal amount of
Bonds of the 8 3/4% Series due 2016 (the fortieth series), $75,000,000 princi-
pal amount of Bonds of the 8 1/4% Series due 2017 (the forty-first series),
$75,000,000 principal amount of Bonds of the 9% Series due 1990 (the forty-sec-
ond series) and $75,000,000 principal amount of Bonds of the 9 3/4% Series due
2019 (the forty-third series), have been heretofore redeemed and retired and
there are now issued and outstanding under the Original Indenture and under the
supplemental indentures referred to above: $40,000,000 principal amount of
Bonds of the 5% Series due 1995 (the fourteenth series); $50,000,000 principal
amount of Bonds of the 4 3/8% Series due 1998 (the fifteenth series);
$45,000,000 principal amount of Bonds of the 4 1/2% Series due 1999 (the six-
teenth series); $15,000,000 principal amount of Bonds of the 5 1/8% Series due
2001 (the seventeenth series); $35,000,000 principal amount of Bonds of the 5
7/8% Series due 2002 (the eighteenth series); $40,000,000 principal amount of
Bonds of the 6 5/8% Series due 2003 (the nineteenth series); $50,000,000 prin-
cipal amount of Bonds of the Adjustable Rate Series due 2001 (the thirty-fourth
series); $59,800,000 principal amount of Bonds of the 8 5/8% Series due 2019
(the forty-fourth series); $100,000,000 principal amount of Bonds of the 9% Se-
ries due 2000 (the forty-fifth series); $100,000,000 principal amount of Bonds
of the 9% Series due 2021 (the forty-sixth series); $75,000,000 principal
amount of Bonds of the 8 1/2% Series due 2027 (the forty-seventh series);
$30,000,000 principal amount of Bonds of the 6% Series due 2022 (the forty-
eighth series); $37,000,000 principal amount of Bonds of the 6 3/8% Series due
2023 (the forty-ninth series); $78,000,000 principal amount of Bonds of the 6
1/2% Series due 2008 (the fiftieth series); $40,000,000 principal amount of
Bonds of the 7 1/2% Series due 2028 (the fifty-first series); $100,000,000
principal amount of Bonds of the 7 1/4% Series due 2023 (the fifty-second se-
ries); $100,000,000 principal amount of Bonds of the 6 7/8% Series due 2023
(the fifty-third series); $50,000,000 principal amount of Bonds of the 5 5/8%
Series due 2003 (the fifty-fourth series); $50,000,000 principal amount of
Bonds of the 5 7/8% Series due 2008 (the fifty-fifth series); $75,000,000 prin-
cipal amount of Bonds of the 6 7/8% Series due 2024 (the fifty-sixth series);
$42,500,000 principal amount of
 
                                       3

 
Bonds of the 5 3/8% Series due 2024 (the fifty-seventh series); $38,300,000
principal amount of Bonds of the 5 3/8% Series due 2024 (the fifty-eighth se-
ries); and $16,000,000 principal amount of Bonds of the 5 3/4% Series due 2010
(the fifty-ninth series); and
 
 Whereas, for the purpose of conforming the Original Indenture to the stan-
dards prescribed by the Trust Indenture Act of 1939 or otherwise modifying
certain of the provisions of the Original Indenture, indentures supplemental
thereto dated December 10, 1939, August 10, 1942, October 15, 1942, April 1,
1966, June 16, 1981, June 17, 1981, December 1, 1981, August 1, 1982, October
1, 1982, April 15, 1983, November 1, 1985, March 1, 1986, November 1, 1986,
March 1, 1987, September 16, 1987, May 1, 1989, August 1, 1989, April 5, 1990,
May 21, 1991, May 7, 1992, September 1, 1992, November 1, 1992, March 1, 1993,
March 2, 1993, July 1, 1993, August 20, 1993, September 29, 1993, September
30, 1993, October 1, 1993, February 10, 1994, February 11, 1994 and March 10,
1995 have been heretofore entered into between the Company and the Trustee,
and for the purpose of conveying additional property, indentures supplemental
thereto dated July 15, 1942, October 15, 1947, December 31, 1948, December 31,
1949, February 15, 1951, February 16, 1953, March 15, 1954, March 15, 1955,
March 15, 1956, April 1, 1957, May 1, 1958, May 1, 1959, May 2, 1960, April 3,
1961, May 1, 1962, May 1, 1963, April 23, 1964, May 3, 1965, June 1, 1966,
April 28, 1967, July 3, 1967, May 1, 1968, June 16, 1969, May 15, 1970, Sep-
tember 1, 1971, June 17, 1981, November 1, 1985, September 16, 1987, May 1,
1989, May 21, 1991, May 7, 1992 and July 1, 1993 have been heretofore entered
into between the Company and the Trustee, and for the purpose of better secur-
ing and protecting the Bonds then or thereafter issued and confirming the lien
of the Original Indenture, an indenture dated October 15, 1942 supplemental
thereto has been heretofore entered into between the Company and the Trustee;
the Original Indenture as heretofore amended and supplemented being hereinaf-
ter referred to as the "Original Indenture as amended"; and
 
 Whereas, the Company is entitled to have authenticated and delivered addi-
tional Bonds on the basis of the net bondable value of property additions,
upon compliance with the provisions of Section 4 of Article III of the Origi-
nal Indenture as amended; and
 
 
                                       4

 
 Whereas, the Company has determined to issue a sixtieth series of Bonds under
the Original Indenture as amended in the principal amount of $    , to be
known as First Mortgage Bonds,  % Series due    (hereinafter called "Bonds of
   Series"); and
 
 Whereas, the Original Indenture as amended provides that certain terms and
provisions, as determined by the Board of Directors of the Company, of the
Bonds of any particular series may be expressed in and provided by the execu-
tion of an appropriate supplemental indenture; and
 
 Whereas, the Original Indenture as amended provides that the Company and the
Trustee may enter into indentures supplemental thereto to add to the covenants
and agreements of the Company contained therein other covenants and agreements
thereafter to be observed; and to surrender any right or power reserved to or
conferred upon the Company in the Original Indenture as amended; and
 
 Whereas, the Company, in the exercise of the powers and authority conferred
upon and reserved to it under the provisions of the Original Indenture as
amended and pursuant to appropriate resolutions of its Board of Directors, has
duly resolved and determined to make, execute and deliver to the Trustee a
Supplemental Indenture in the form hereof for the purposes herein provided;
and
 
 Whereas, all conditions and requirements necessary to make this Supplemental
Indenture a valid, binding and legal instrument have been done, performed and
fulfilled, and the execution and delivery hereof have been in all respects
duly authorized;
 
 Now, Therefore, This Indenture Witnesseth:
 
 That Potomac Electric Power Company, in consideration of the premises and of
One Dollar to it duly paid by the Trustee at or before the ensealing and de-
livery of these presents, and for other valuable considerations, the receipt
whereof is hereby acknowledged, hereby covenants, declares and agrees with the
Trustee and its successors in the trust under the Original Indenture as amend-
ed, for the benefit of those who hold the Bonds and coupons, or any of them,
issued or to be issued hereunder or under the Original Indenture as amended,
as follows:
 
 
                                       5

 
                                    PART I.
 
                             Description of Bonds.
 
 Section 1. The Bonds of    Series shall, subject to the provisions of Section
1 of Article II of the Original Indenture as amended, be designated as "First
Mortgage Bonds,  % Series due   " of the Company. The Bonds of    Series shall
be executed, authenticated and delivered in accordance with the provisions of,
and shall in all respects be subject to, all of the terms, conditions and cov-
enants of the Original Indenture as amended, except in so far as the terms and
provisions of the Original Indenture as amended are amended or modified by
this Supplemental Indenture.
 
 The Bonds of    Series shall mature     , and shall bear interest at the rate
of      per cent ( %) per annum, payable semiannually, commencing    , on the
fifteenth day of   and the fifteenth day of     in each year (each such     15
and     15 being hereinafter called an "interest payment date"). The Bonds of
   Series shall be payable as to principal and interest in lawful money of the
United States of America, and shall be payable (as well the interest as the
principal thereof) at the Agency of the Company in the City of Washington,
D.C., or at the Agency of the Company in the Borough of Manhattan, The City of
New York.
 
 The interest so payable on any interest payment date shall be paid to the
persons in whose names the Bonds of    Series are registered at the close of
business on the last business day (hereinafter called the "record date") which
is more than ten days prior to such interest payment date, a "business day"
being any day that is not a day on which banks in the City of Washington,
D.C., are authorized by law to close; except that if the Company shall default
in the payment of any interest due on such interest payment date, such de-
faulted interest shall be paid to the persons in whose names the Bonds of
Series are registered on the date of payment of such defaulted interest, or in
accordance with the regulations of any securities exchange on which the Bonds
of    Series are listed.
 
 Except as provided hereinafter, every Bond of    Series shall be dated as of
the date of its authentication and delivery, or if that is an
 
                                       6

 
interest payment date, the next day, and shall bear interest from the interest
payment date next preceding its date or the date of delivery of the initial
Bonds of    Series, whichever is later. Notwithstanding Section 6 of Article
II of the Original Indenture, any Bond of    Series authenticated and deliv-
ered by the Trustee after the close of business on the record date with re-
spect to any interest payment date and prior to such interest payment date
shall be dated as of the date next following such interest payment date and
shall bear interest from such interest payment date; except that if the Com-
pany shall default in the payment of any interest due on such interest payment
date, such Bond shall bear interest from the next preceding interest payment
date or the date of delivery of the initial Bonds of    Series, whichever is
later.
 
 Section 2. The Bonds of    Series, and the Trustee's certificate to be en-
dorsed on the Bonds of    Series, shall be substantially in the following
forms, respectively:
 
                      [form of face of bond of    series]
 
                        POTOMAC ELECTRIC POWER COMPANY
               (A District of Columbia and Virginia corporation)
 
                     First Mortgage Bond,  % Series Due
 
No.                                                                        $
 
 Potomac Electric Power Company, a corporation organized and existing under
the laws of the District of Columbia and a domestic cor- poration of the Com-
monwealth of Virginia (hereinafter called the "Company", which term shall in-
clude any successor corporation as defined in the Amended Indenture hereinaf-
ter referred to), for value received, hereby promises to pay to
 ................... or registered assigns, the sum of .................. dol-
lars, on the fifteenth day of       , in lawful money of the United States of
America, and to pay interest thereon in like money from the later of the date
of delivery of the initial Bonds of    Series or the interest payment date
15 or     15 next preceding the date of this Bond, or if the Company shall de-
fault in the payment of interest due on such interest payment date, then from
the
 
                                       7

 
next preceding interest payment date or the date of delivery of the initial
Bonds of    Series, whichever is later, at the rate of         percent ( %)
per annum, payable semiannually, commencing      , 1996, on the fifteenth day
of     and     in each year until maturity, or, if the Company shall default
in the payment of the principal hereof, until the Company's obligation with
respect to the payment of such principal shall be discharged as provided in
the Amended Indenture. The interest so payable on any     15 or     15 will,
subject to certain exceptions provided in the indenture dated as of       sup-
plemental to the Amended Indenture, be paid to the person in whose name this
Bond is registered at the close of business on the last business day which is
more than ten days prior to such     15 or     15. Both principal of, and in-
terest on, this Bond are payable at the agency of the Company in the City of
Washington, D.C., or, at the option of the holder, at the agency of the Com-
pany in the Borough of Manhattan, The City of New York.
 
 Reference is made to the further provisions of this Bond set forth on the re-
verse hereof, and such further provisions shall for all purposes have the same
effect as though fully set forth at this place.
 
 This Bond shall not be entitled to any benefit under the Amended Indenture or
any indenture supplemental thereto, or become valid or
obligatory for any purpose, until The Riggs National Bank of Washington, D.C.,
the Trustee under the Amended Indenture, or a successor trustee thereto under
the Amended Indenture, shall have signed the form of certificate endorsed
hereon.
 
                                       8

 
 In Witness Whereof, Potomac Electric Power Company has caused this Bond to be
signed in its name by the signature (or a facsimile thereof) of its President
or a Vice President, and its corporate seal (or a facsimile thereof) to be
hereto affixed and attested by the facsimile signature of its Secretary or an
Assistant Secretary.
 
 Dated,
 
                                 Potomac Electric Power Company
 
                                       By......................................
                                                     Vice President
Attest:
 
 ...................................
             Secretary
 
                                       9

 
                        [FORM OF TRUSTEE'S CERTIFICATE]
 
 This Bond is one of the Bonds, of the series designated therein, described in
the within-mentioned Amended Indenture and the Supplemental Indenture dated as
of       .
 
                                    The Riggs National Bank of Washington, D.C.
                                                                       Trustee.
 
                                   By..........................................
                                                 Authorized Officer
 
             [TEXT APPEARING ON REVERSE SIDE OF BOND OF    SERIES]
 
 This Bond is one of a duly authorized issue of Bonds of the Company (herein-
after called the "Bonds") in unlimited aggregate principal amount, of the se-
ries hereinafter specified, all issued and to be issued under and equally se-
cured (except in so far as any purchase or sinking fund or analogous provi-
sions for any particular series of Bonds, established by any indenture supple-
mental to the Amended Indenture hereinafter mentioned, may afford additional
security for such Bonds) by a mortgage and deed of trust, dated July 1, 1936,
executed by the Company to The Riggs National Bank of Washington, D.C. (herein
called the "Trustee"), as trustee, as amended by indentures supplemental
thereto dated December 10, 1939, August 10, 1942, October 15, 1942, April 1,
1966, June 16, 1981, June 17, 1981, December 1, 1981, August 1, 1982, October
1, 1982, April 15, 1983, November 1, 1985, March 1, 1986, November 1, 1986,
March 1, 1987, September 16, 1987, May 1, 1989, August 1, 1989, April 5, 1990,
May 21, 1991, May 7, 1992, September 1, 1992, November 1, 1992, March 1, 1993,
March 2, 1993, July 1, 1993, August 20, 1993, September 29, 1993, September
30, 1993, October 1, 1993, February 10, 1994, February 11, 1994 and March 10,
1995 (said mortgage and deed of trust, as so amended, being herein called the
"Amended Indenture") and all indentures supplemental thereto, to which Amended
Indenture and supplemental indentures reference is hereby made for a descrip-
tion of the properties mortgaged and pledged, the nature and extent of the se-
curity, the rights of the owners of the Bonds and of the Trustee in respect
thereto, and the
 
                                      10

 
terms and conditions upon which the Bonds are, and are to be, secured. To the
extent permitted by, and as provided in, the Amended Indenture, modifications
or alterations of the Amended Indenture, or of any indenture supplemental
thereto, and of the rights and obligations of the Company and of the holders
of the Bonds may be made with the consent of the Company by an affirmative
vote of not less than 80% in amount of the Bonds entitled to vote then out-
standing, at a meeting of Bondholders called and held as provided in the
Amended Indenture, and by an affirmative vote of not less than 80% in amount
of the Bonds of any series entitled to vote then outstanding and affected by
such modification or alteration, in case one or more but less than all of the
series of Bonds then outstanding under the Amended Indenture are so affected;
provided, however, that no such modification or alteration shall be made which
will affect the terms of payment of the principal of, or interest on, this
Bond, which are unconditional, or which reduces the percentage of Bonds the
affirmative vote of which is required for the making of such modifications or
alterations. The Company is proposing an amendment to the Amended Indenture
which would replace "80%" with "60%" in the preceding sentence, which amend-
ment will become effective upon the consent or agreement thereto of the hold-
ers of all the outstanding Bonds. The holder of this Bond will be deemed to
have approved such amendment. The Bonds may be issued in series, for various
principal sums, may mature at different times, may bear interest at different
rates and may otherwise vary as in the Amended Indenture provided.
 
 This Bond is one of a series designated as the "First Mortgage Bonds,  % Se-
ries due   " (herein called the "Bonds of    Series") of the Company, issued
under and secured by the Amended Indenture and all indentures supplemental
thereto and described in the indenture (herein called the "New Supplemental
Indenture"), dated as of       , between the Company and the Trustee, supple-
mental to the Amended Indenture.
 
 The Bonds of    Series are subject to redemption, at any time or from time to
time after        and prior to maturity, at the option of the Company, either
as a whole or in part by lot, upon payment of the redemption prices applicable
to the respective period set forth below, together, in each case, with accrued
interest to the redemption
 
                                      11

 
date, all subject to the conditions and as more fully set forth in the Amended
Indenture and the New Supplemental Indenture:
 


                  REDEMPTION PRICE
   IF REDEEMED      EXPRESSED AS
   DURING THE      PERCENTAGE OF
 12 MONTH PERIOD   THE PRINCIPAL
   ENDING         AMOUNT OF BONDS
 ---------------  ----------------
               
  ...............          %
  ...............
  ...............
  ...............
  ...............
  ...............



                         REDEMPTION PRICE
      IF REDEEMED          EXPRESSED AS
       DURING THE         PERCENTAGE OF
    12 MONTH PERIOD       THE PRINCIPAL
      ENDING             AMOUNT OF BONDS
    ---------------      ----------------
                      
  ......................            %
  ......................
  ......................
  ......................
   and thereafter.......      100.00

 
 Notice of any redemption shall be sent by the Company through the mails,
postage prepaid, at least thirty days and not more than sixty days prior to
the redemption date, to the registered owners of any of the Bonds to be re-
deemed, at their addresses as the same shall appear on the transfer register
of the Company, all subject to the conditions and as more fully set forth in
the Amended Indenture and New Supplemental Indenture. Any notice so mailed
shall be conclusively presumed to have been duly given, whether or not the
owner receives it.
 
 In case an event of default, as defined in the Amended Indenture, shall oc-
cur, the principal of all the Bonds at any such time outstanding under the
Amended Indenture may be declared or may become due and payable, upon the con-
ditions and in the manner and with the effect provided in the Amended Inden-
ture. The Amended Indenture provides that such declaration may in certain
events be waived by the holders of a majority in principal amount of the Bonds
entitled to vote then outstanding.
 
 This Bond is transferable by the registered owner hereof, in person or by
duly authorized attorney, on the books of the Company to be kept for that pur-
pose at the agency of the Company in the City of Washington, D.C., or at the
agency of the Company in the Borough of Manhattan, The City of New York, upon
surrender and cancellation of this Bond and on presentation of a duly executed
written instrument of transfer, and thereupon a new Bond or Bonds of the same
series, of the same aggregate principal amount and in authorized denominations
will be issued to the transferee or transferees in exchange therefor; and this
Bond, with or without others of the same series, may in like manner be ex-
changed
 
                                      12

 
for one or more new Bonds of the same series of other authorized denominations
but of the same aggregate principal amount; all subject to the terms and con-
ditions set forth in the Amended Indenture.
 
 No recourse shall be had for the payment of the principal of, or the interest
on, this Bond, or for any claim based hereon or otherwise in respect hereof or
of the Amended Indenture or any indenture supplemental thereto, against any
incorporator, or against any stockholder, director or officer, past, present
or future, of the Company or of any predecessor or successor corporation, ei-
ther directly or through the Company or any such predecessor or successor cor-
poration, whether for amounts unpaid on stock subscriptions or by virtue of
any constitution, statute or rule of law, or by the enforcement of any assess-
ment or penalty or otherwise, all such liability, whether at common law, in
equity, by any constitution, statute or otherwise, of incorporators, stock-
holders, directors or officers being released by every owner hereof by the ac-
ceptance of this Bond and as part of the consideration for the issue hereof,
and being likewise released by the terms of the Amended Indenture.
 
 Section 3. The Bonds of    Series shall be registered Bonds without coupons
in denominations of any multiple of $1,000, numbered consecutively upwards
from R1.
 
 Section 4. Until Bonds of    Series in definitive form are ready for deliv-
ery, the Company may execute, and upon its request in writing the Trustee
shall authenticate and deliver, in lieu thereof, Bonds for such series in tem-
porary form, as provided in Section 9 of Article II of the Original Indenture
as amended.
 
                                   PART II.
 
                                Issue of Bonds.
 
 Section 1. Except for Bonds of    Series issued pursuant to Section 13 of Ar-
ticle II of the Original Indenture as amended, the principal amount of Bonds
of    Series which may be authenticated and delivered hereunder is limited to
$     aggregate principal amount.
 
 
                                      13

 
 Section 2. Bonds of    Series in the aggregate principal amount permitted in
Section 1 of this Part II, may at any time subsequent to the execution hereof
be executed by the Company and delivered to the Trustee and shall be authenti-
cated by the Trustee and delivered (either before or after the recording here-
of) to or upon the order of the Company evidenced by a writing or writings,
signed by its President or one of its Vice Presidents and its Treasurer or one
of its Assistant Treasurers, at such time or times as may be requested by the
Company subsequent to the receipt by the Trustee of
 
  (1) the certified resolution and the officers' certificate required by Sec-
 tion 3(a) and Section 3(b) of Article III of the Original Indenture as
 amended;
 
  (2) the opinion of counsel required by Section 3(c) of Article III of the
 Original Indenture as amended;
 
  (3) cash, if any, in the amount required to be deposited by Section 3(d) of
 Article III of the Original Indenture as amended, which shall be held and
 applied by the Trustee as provided in said Section 3(d);
 
  (4) the certificates, instruments, opinions of counsel, prior lien bonds
 and cash, if any, required by Section 4 of Article III of the Original In-
 denture as amended, except that, as required by Part IV of this Supplemental
 Indenture, property additions purchased, constructed or otherwise acquired
 on or before December 31, 1946 shall not be made the basis for the authenti-
 cation and delivery of Bonds of    Series; and
 
  (5) the certificates and opinions required by Article XVIII of the Original
 Indenture as amended.
 
                                   PART III.
 
                                  Redemption.
 
 Section 1. The Bonds of    Series are not redeemable up to and including
     . The Bonds of    Series shall, in accordance with the provisions of Ar-
ticle V of the Original Indenture as amended, be redeemable, at any time or
from time to time after       and prior to maturity, at the option of the
Board of Directors of the
 
                                      14

 
Company, either as a whole or in part by lot, upon payment of the redemption
prices applicable to the respective periods set forth in the form of Bond of
   Series contained in Section 2 of Part I hereof, together, in each case,
with accrued interest to the redemption date.
 
 Section 2. In accordance with the provisions of Article V of the Original In-
denture as amended, notice of any redemption shall be sent by the Company
through the mails, postage prepaid, at least thirty days and not more than
sixty days prior to the date of redemption, to the registered owners of any of
the Bonds to be redeemed at their addresses as the same shall appear on the
transfer register of the Company. Any notice so mailed shall be conclusively
presumed to have been duly given, whether or not the owner receives it.
 
 All Bonds delivered to or redeemed by the Trustee pursuant to the provisions
of this Part III shall forthwith be cancelled.
 
                                   PART IV.
 
                Additional Particular Covenants of the Company.
 
 The Company hereby covenants, warrants and agrees that so long as any Bonds
of    Series are outstanding:
 
 Section 1. The Company will not withdraw, pursuant to the provisions of Sec-
tion 2 of Article VIII of the Original Indenture as amended, any moneys held
by the Trustee as part of the trust estate in excess of an amount equal to the
aggregate principal amount of such of the refundable Bonds as were theretofore
issued by the Company; and that upon any such withdrawal by the Company re-
fundable Bonds equal in aggregate principal amount to the amount so withdrawn
shall be deemed to have been made the basis of such withdrawal.
 
 Section 2. Property additions purchased, constructed or otherwise acquired on
or before December 31, 1946 shall not be made the basis for the authentication
and delivery of Bonds, or the withdrawal of cash, or the reduction of the
amount of cash required to be paid to the Trustee under any provision of the
Indenture.
 
 
                                      15

 
                                    PART V.
 
                Amendment of Indenture to Permit Qualification
                      Under Trust Indenture Act of 1939.
 
 The Company and the Trustee, from time to time and at any time, without any
vote or consent of the holders of the Bonds of    Series, may enter into such
indentures supplemental to the Original Indenture as may or shall by them be
deemed necessary or desirable to add to or modify or amend any of the provi-
sions of the Original Indenture so as to permit the qualification of the Orig-
inal Indenture under the Trust Indenture Act of 1939.
 
 Except to the extent specifically provided herein, no provision of this Sup-
plemental Indenture is intended to modify, and the parties hereto do hereby
adopt and confirm, the provisions of Section 318(c) of the Trust Indenture Act
of 1939 which amend and supersede provisions of the Original Indenture, as
supplemented, in effect prior to November 15, 1990.
 
                                   PART VI.
 
                       Amendment of Original Indenture.
 
 Notwithstanding any other provisions of the Original Indenture as amended,
the holders of the Bonds of    Series, by their holding of such Bonds, are
deemed to have approved the following amendment to the Original Indenture as
amended and to have authorized the Trustee to take any action necessary to ev-
idence or effectuate such approval:
 
 Sections 5 and 6 of Article XV of the Original Indenture as amended are
 hereby amended by changing the words and figures "eighty percent. (80%)" to
 the words and figures "sixty percent. (60%)" wherever in such Sections such
 words and figures occur.
 
                                   PART VII.
 
                                 The Trustee.
 
 The Trustee hereby accepts the trusts hereby declared and provided and agrees
to perform the same upon the terms and conditions in the
 
                                      16

 
Original Indenture as amended set forth and upon the following terms and con-
ditions:
 
 The Trustee shall not be responsible in any manner whatsoever for or in re-
spect of the validity or sufficiency of this Supplemental Indenture or the due
execution hereof by the Company or for or in respect of the recitals contained
herein, all of which recitals are made by the Company solely. In general, each
and every term and condition contained in Article XIII of the Original Inden-
ture as amended shall apply to this Supplemental Indenture with the same force
and effect as if the same were herein set forth in full, with such omissions,
variations and modifications thereof as may be appropriate to make the same
conform to this Supplemental Indenture.
 
                                  PART VIII.
 
                           Miscellaneous Provisions.
 
 This Supplemental Indenture may be simultaneously executed in any number of
counterparts, each of which when so executed shall be deemed to be an origi-
nal; but such counterparts shall together constitute but one and the same in-
strument.
 
 Potomac Electric Power Company hereby constitutes and appoints Dennis R.
Wraase, one of its Senior Vice Presidents, to be its true and lawful attorney-
in-fact, for it and in its name to appear before any officer authorized by law
to take and certify acknowledgments of deeds to be recorded in the District of
Columbia, in the State of Maryland, in the Commonwealth of Virginia, and in
the Commonwealth of Pennsylvania and to acknowledge and deliver these presents
as the act and deed of said Potomac Electric Power Company.
 
 The Riggs National Bank of Washington, D.C., hereby constitutes and appoints
James B. Lynn, one of its Vice Presidents, to be its true and lawful attorney-
in-fact, for it and in its name to appear before any officer authorized by law
to take and certify acknowledgments of deeds to be recorded in the District of
Columbia, in the State of Maryland, in the Commonwealth of Virginia, and in
the Commonwealth of Pennsylvania and to acknowledge and deliver these presents
as the act and deed of said The Riggs National Bank of Washington, D.C.
 
                                      17

 
 In Witness Whereof, said Potomac Electric Power Company has caused this Sup-
plemental Indenture to be executed on its behalf by its President or one of
its Vice Presidents and its corporate seal to be hereto affixed and said seal
and this Supplemental Indenture to be attested by its Secretary or one of its
Assistant Secretaries; and said The Riggs National Bank of Washington, D.C.,
in evidence of its acceptance of the trust hereby created, has caused this
Supplemental Indenture to be executed on its behalf by its President or one of
its Senior Vice Presidents, and its corporate seal to be hereto affixed and
said seal and this Supplemental Indenture to be attested by one of its Corpo-
rate Trust Officers, all as of the   day of    , One thousand nine hundred and
ninety-five.
 
                                                 Potomac Electric Power Company
(Corporate Seal)
                                    By.........................................
                                                  DENNIS R. WRAASE,
                                                Senior Vice President
Attested:
 
 ...................................
       ELLEN SHERIFF ROGERS,
        Assistant Secretary
  Signed, sealed and delivered by
 Potomac Electric Power Company in
         the presence of:
 
 ...................................
 
 ...................................
                       As Witnesses
                                   The Riggs National Bank of Washington, D.C.
(Corporate Seal)
                                   By..........................................
                                                   JAMES B. LYNN,
                                                   Vice President
Attested:
 
 ...................................
      O. CLINTON JONES, III,
  Senior Corporate Trust Officer
Signed, sealed and delivered by The
 Riggs National Bank of Washington,
      D.C. in the presence of:
 
 ...................................
 
 ...................................
                       As Witnesses
 
                                      18

 
City of Washington,         )
District of Columbia,       )   ss.:

 I,      , a Notary Public in and for the District of Columbia, United States
of America, whose commission as such will expire        , do hereby certify
that Dennis R. Wraase and Ellen Sheriff Rogers, whose names as Senior Vice
President and Assistant Secretary, respectively, of Potomac Electric Power
Company, a corporation, are signed to the foregoing and hereto attached deed,
bearing date as of the   day of      , personally appeared this day before me
in my District aforesaid and acknowledged themselves to be, respectively, a
Senior Vice President and an Assistant Secretary of Potomac Electric Power
Company, and that they as such, being authorized so to do, executed the said
deed by signing the name of Potomac Electric Power Company by Dennis R.
Wraase, as Senior Vice President, and attested by Ellen Sheriff Rogers, as As-
sistant Secretary, and acknowledged the same before me in my District afore-
said and acknowledged the foregoing instrument to be the act and deed of Poto-
mac Electric Power Company.
 
 Given under my hand and official seal this   day of      .
 
(Notarial Seal)
 
                                   ............................................
                                                  Notary Public
                                               District of Columbia
 
                                      19

 
City of Washington,          )
District of Columbia,        )  ss.:
 
 I,      , a Notary Public in and for the District of Columbia, United States
of America, do hereby certify that Dennis R. Wraase, a Senior Vice President
of Potomac Electric Power Company, a corporation, one of the parties to the
foregoing instrument bearing date as of the   day of      , and hereto an-
nexed, this day personally appeared before me in the City of Washington, the
said Dennis R. Wraase being personally well known to me as the person who exe-
cuted the said instrument as a Senior Vice President of and on behalf of said
Potomac Electric Power Company and known to me to be the attorney-in-fact duly
appointed therein to acknowledge and deliver said instrument on behalf of said
corporation, and, as such attorney-in-fact, he acknowledged said instrument to
be the act and deed of said Potomac Electric Power Company, and delivered the
same as such. I further certify that the said Dennis R. Wraase, being by me
duly sworn, did depose and say that he knows the seal of said corporation;
that the seal affixed to said instrument is such corporate seal and was so af-
fixed by order of the Board of Directors of said corporation; and that he
signed his name thereto by like order. My commission expires      .
 
 Given under my hand and official seal this   day of      .
 
(Notarial Seal)
 
                                   ............................................
                                                  Notary Public
                                               District of Columbia
 
                                      20

 
City of Washington,          )
District of Columbia,        )   ss.:
 
 I,      , a Notary Public in and for the District of Columbia, United States
of America, do hereby certify that James B. Lynn and O. Clinton Jones, III,
whose names as Vice President and Senior Corporate Trust Officer, respective-
ly, of The Riggs National Bank of Washington, D.C., a corporation, are signed
to the foregoing and hereto attached deed, bearing date as of the   day of
     , personally appeared before me this day in my District aforesaid and ac-
knowledged themselves to be, respectively, a Vice President and a Senior Cor-
porate Trust Officer of The Riggs National Bank of Washington, D.C., and that
they as such, being authorized so to do, executed the said deed by signing the
name of The Riggs National Bank of Washington, D.C., by James B. Lynn as Vice
President, and attested by O. Clinton Jones, III, as Senior Corporate Trust
Officer, and acknowledged the same before me in my District aforesaid and ac-
knowledged the foregoing instrument to be the act and deed of The Riggs Na-
tional Bank of Washington, D.C., as therein set forth.
 
 Given under my hand and notarial seal this   day of       .
 
(Notarial Seal)
 
                                ...............................................
                                                 Notary Public
                                             District of Columbia
 
                                My Commission Expires      .
 
                                      21

 
City of Washington,          )
District of Columbia,        )  ss.:
 
 James B. Lynn, of full age, being sworn according to law, on his oath deposes
and says that he is a Vice President of The Riggs National Bank of Washington,
D.C., the Trustee named in the foregoing Supplemental Indenture, dated as of
the   day of      , that he is the agent of said Trustee for the purpose of
perfecting such Supplemental Indenture and that the consideration in the Orig-
inal Indenture referred to therein and in all indentures supplemental to said
Original Indenture, including the foregoing Supplemental Indenture, is true
and bona fide as therein set forth.
 
                                   ............................................
                                                  JAMES B. LYNN
 
Subscribed and sworn to before me
  this   day of       .
 
 ...................................
           Notary Public
       District of Columbia
 
 My Commission Expires      .
 
(Notarial Seal)
 
                                      22

 
City of Washington,          )
District of Columbia,        )  ss.:
 
 I,      , a Notary Public in and for the District of Columbia, United States
of America, do hereby certify that James B. Lynn a Vice President of The Riggs
National Bank of Washington, D.C., a corporation, one of the parties to the
foregoing instrument bearing date as of the    day of     , and hereto an-
nexed, this day personally appeared before me in the City of Washington, the
said James B. Lynn, being personally well known to me as the person who exe-
cuted the said instrument as a Vice President of and on behalf of said The
Riggs National Bank of Washington, D.C., and known to me to be the attorney-
in-fact duly appointed therein to acknowledge and deliver said instrument on
behalf of said corporation, and, as such attorney-in-fact, he acknowledged
said instrument to be the act and deed of said The Riggs National Bank of
Washington, D.C., and delivered the same as such. I further certify that the
said James B. Lynn, being by me duly sworn, did depose and say that he knows
the seal of said corporation; that the seal affixed to said instrument is such
corporate seal and was so affixed by order of the Board of Directors of said
corporation; and that he signed his name thereto by like order.
 
 Given under my hand and official seal this    day of      .
 
(Notarial Seal)
 
                                ...............................................
                                                 Notary Public
                                             District of Columbia
 
                                My Commission Expires      .
 
                                      23

 
                           CERTIFICATE OF RESIDENCE
 
 The Riggs National Bank of Washington, D.C., Mortgagee and Trustee within
named, hereby certifies that its precise residence is 800-17th Street, N.W.,
Washington, D.C. 20006.
 
                                   The Riggs National Bank of Washington, D.C.
 
                                   By..........................................
                                                  JAMES B. LYNN,
                                                  Vice President
 
                                      24