CERTIFICATE OF INCORPORATION


                                       OF


                                  BL GAS, INC.


        (Pursuant to Section three of the Transportation Corporations Law
                            of the State of New York)


     I, the undersigned,  being a natural person of at least eighteen (18) years
of age and acting  for the  purpose of  forming a gas  corporation  pursuant  to
section three of the  Transportation  Corporations  Law of the State of New York
and under Section 402 of the Business  Corporation Law of the State of New York,
hereby CERTIFY that:

     FIRST: The name of the corporation shall be: BL Gas, Inc.

     SECOND:  The purpose of the corporation is to produce or otherwise  acquire
and to supply  for  public use  artificial  or natural  gas or a mixture of both
gases for  light,  heat or power and for  lighting  the  streets  and public and
private buildings of cities,  villages and towns in the State of New York and to
engage in any lawful act or activity for which gas corporations may be organized
under the  Transportation  Corporations Law and the Business  Corporation Law of
the State of New York ,  provided  that it is not formed to engage in any act or
activity  requiring the consent or approval of any state  official,  department,
board,  agency or other body  without  such  consent  or  approval  first  being
obtained.

     THIRD:  The  office of the  corporation  shall be  located in the County of
Nassau, State of New York.

     FOURTH: The aggregate number of shares which the corporation shall have the
authority to issue shall be 100. Such shares shall consist of one class,  herein
designated as common stock, of the par value of $.01 per share.

     FIFTH: The Secretary of State of the State of New York is hereby designated
as agent of the corporation upon whom process against it may be served,  and the
post  office  address to which the  Secretary  of State shall mail a copy of any
process against it served upon him is 175 East Old Country Road, Hicksville, New
York 11801. Attention: Secretary.

     SIXTH:  The  corporation  shall be a gas  corporation  and shall operate in
Nassau


<PAGE>



     County, New York, Suffolk County, New York and Queen's County, New York.

     SEVENTH: The duration of the corporation shall be perpetual.

     EIGHTH: No director shall be personally liable to the corporation or any of
its  shareholders for damages for any breach of duty in such capacity except for
liability if a judgment or other final  adjudication  adverse to him establishes
(A) that his act or omissions (I) were in bad faith,  (ii) involved  intentional
misconduct,  or (iii)  involved a knowing  violation  of the law, or (B) that he
personally  gained in fact a financial profit or other advantage to which he was
not legally entitled,  or (C) that his acts violated Section 719 of the Business
Corporation  Law of the State of New York. This provision shall not eliminate or
limit the personal  liability  of any director for any act or omission  prior to
the adoption of this provision.  If the Business Corporation Law of the State of
New York is  amended  to  authorize  corporate  action  further  eliminating  or
limiting the personal  liability of directors,  then the liability of a director
of the  corporation  shall  be  eliminated  or  limited  to the  fullest  extent
permitted  by the  Business  Corporation  Law of the  State of New  York,  as so
amended.

     NINTH: The corporation may, to the fullest extent permitted by Sections 721
through 726 of the Business  Corporation Law of the State of New York, indemnify
any and all directors  and officers whom it shall have power to indemnify  under
the said sections from and against any and all of the expenses,  liabilities  or
other matters referred to in or covered by such section, and the indemnification
provided for herein  shall not be deemed  exclusive of any other rights to which
the  persons  so  indemnified  may  be  entitled  under  any  by-law,   vote  of
shareholders,  or disinterested  directors,  agreement or otherwise,  both as to
action in his  official  capacity  and as to action in any other  capacity  as a
result of holding such office,  and shall continue as to a person who has ceased
to be a  director  or  officer  and shall  inure to the  benefit  of the  heirs,
executors and administrators of such a person.

            IN WITNESS  WHEREOF,  I have signed this Certificate and affirm that
the statements made herein are true under the penalties of perjury, this 6th day
of May, 1998.



                                          /s/ Thomas D. Balliett
                                          ----------------------
                                          Thomas D. Balliett, Esq.
                                          Sole Incorporator
                                          Kramer, Levin, Naftalis
                                                & Frankel
                                          919 Third Avenue
                                          New York, New York 10022





<PAGE>





                            CERTIFICATE OF AMENDMENT


                                     OF THE


                          CERTIFICATE OF INCORPORATION


                                       OF


                                  BL GAS, INC.


                Under Section 805 of the Business Corporation law
                            of the State of New York



     BL Gas,  Inc., a corporation  organized and existing  under the laws of the
State of New York (the "Corporation"), does hereby certify as follows:

     FIRST: The name of the Corporation is BL Gas, Inc.

     SECOND:  The certificate of  incorporation  of the Corporation was filed by
the New York Department of State on May 7, 1998.

     THIRD: The certificate of incorporation is hereby amended (I) to change the
name of the Corporation as authorized by the New York Business  Corporation Law,
to wit:

            Article I relating to the name of the Corporation is amended to read
      in its entirety as follows:

      "FIRST: The name of the corporation shall be: MarketSpan Gas Corporation."

     FOURTH:  The foregoing  amendment to the certificate of  incorporation  has
been duly  adopted by a Unanimous  Written  Consent of the Board of Directors of
the  Corporation and by a Unanimous  Written Consent of the  shareholders of the
Corporation, in accordance with Section 803 of the New York Business Corporation
Law.




<PAGE>



            IN WITNESS WHEREOF, the undersigned officers of the Corporation have
signed this  Certificate of Amendment and each affirms that the statements  made
herein are true under the penalties of perjury.

Dated:   May 26, 1998

                                          BL GAS, INC.

                                          By: /s/Kathleen A. Marion
                                          -------------------------
                                          Name: Kathleen A. Marion
                                          Title Vice President & Secretary


<PAGE>



               VERIFICATION OF SIGNER OF CERTIFICATE OF AMENDMENT
                                       FOR
                                  BL GAS, INC.

STATE OF NEW YORK       )
                        ) SS.:
COUNTY OF NEW YORK      )

      Kathleen A.  Marion,  being duly  sworn,  deposes and says that she is the
person who signed the  foregoing  certificate  of  amendment  of the articles of
organization;  that she signed the said articles in the capacity set opposite or
beneath her signature thereon; that she has read the said articles and knows the
contents thereof;  and that the statements contained therein are true to her own
knowledge.


                                          /s/ Kathleen A. Marion
                                          ----------------------
                                          Kathleen A. Marion
                                          Authorized Person

Subscribed and sworn to before me
on May 26, 1998


/s/
-------------
Notary Public



<PAGE>



                            CERTIFICATE OF AMENDMENT
                                     OF THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                           MARKETSPAN GAS CORPORATION

                Under Section 805 of the Business Corporation Law
                            of the State of New York


      The  undersigned,  acting  as  an  authorized  person  of  MarketSpan  Gas
Corporation  (the  "Corporation")  hereinafter  named,  set forth the  following
statements.

     FIRST: The name of the Corporation is MarketSpan Gas Corporation.

     SECOND:  The Certificate of  Incorporation  of the Corporation was filed by
the New York  Department  of State on May 7, 1998.  The first  amendment  to the
Certificate of  Incorporation  was filed by the New York  Department of State on
May 27, 1998. It incorporated under the name of BL Gas, Inc.

     THIRD:  The  Certificate of  Incorporation  is hereby amended to change the
name of the Corporation as authorized by the New York Business  Corporation Law,
to wit:

            Article I relating to the name of the Corporation is amended to read
      in its entirety as follows:

            "FIRST:     The name of the corporation shall be KeySpan Gas East
                  Corporation."

     FOURTH:  The foregoing  amendment to the certificate of  incorporation  has
been duly  adopted by a Unanimous  Written  Consent of the Board of Directors of
the  Corporation and by a Unanimous  Written Consent of the  shareholders of the
Corporation, in accordance with Section 803 of the New York Business Corporation
Law.

      IN WITNESS WHEREOF,  the undersigned officer of the Corporation has signed
this  Certificate of Amendment and affirms that the  statements  made herein are
true and correct under the penalties of perjury.

Dated: October 19, 1998


                                          MARKETSPAN GAS CORPORATION


                                          By:  /s/Robert D. Ekholm
                                               -------------------
                                                Robert D. Ekholm
                                                Secretary