Registration Statement on Form S-3
                                                                     Exhibit 5



                                    January 19, 2000



KeySpan Corporation
d/b/a KeySpan Energy
One MetroTech Center
Brooklyn, NY 11201

KeySpan Gas East Corporation
d/b/a Brooklyn Union of Long Island
175 East Old Country Road
Hicksville, NY 11801

Ladies and Gentlemen:

     I am Senior Vice President and Deputy General Counsel of KeySpan
Corporation d/b/a KeySpan Energy, a New York corporation ("KeySpan") and
counsel to KeySpan Gas East Corporation d/b/a Brooklyn Union of Long Island,
a New York Corporation and a direct, wholly-owned subsidiary of KeySpan
("BULI," and collectively with KeySpan the "Registrants").  I have acted in
such capacities in connection with the Registration Statement on Form S-3, as
amended (the "Registration Statement"), filed on December 2, 1999, by KeySpan
and BULI with the Securities and Exchange Commission (the "Commission") under
the Securities Act of 1933, as amended (the "Act") relating to the issuance,
as described in the Registration Statement, of (1) up to $600,000,000 of
BULI's debt securities (the "Debt Securities"), and (2) the guarantees of
KeySpan which will be issued in connection with the Debt Securities (the
"Guarantees").

     Each series of Debt Securities will be issued under, and the Guarantee
of KeySpan applicable thereto will be set forth in, an Indenture (the
"Indenture") dated as of December 1, 1999, by and among KeySpan, as
guarantor, BULI, as issuer, and The Chase Manhattan Bank, as trustee (the
"Trustee").  A copy of such Indenture has been filed as an Exhibit to the
Registration Statement.

     As counsel to the Registrants, I have participated in and am familiar
with the corporate proceedings of the Registrants relating to the preparation
of the Registration Statement, and any amendments thereto, providing for the
registration of the Debt Securities, and the Guarantee applicable thereto,
for offering and sale on a delayed or continuous basis under the Act and Rule
415 promulgated thereunder.



     In connection with the foregoing, either I or individuals under my
supervision have researched such questions of law and examined the originals
or copies of the Registration Statement and the Indenture and such corporate
records, agreements or other instruments of the Registrants and other
instruments and documents as I have deemed relevant and necessary in
connection with the opinions hereinafter expressed.  As to various questions
of fact material to such opinions, I have, where relevant facts were not
independently established by me, relied upon statements of other officers of
the Registrants, whom I believe to be responsible.

     In rendering the opinions set forth below, I have assumed the
genuineness of all signatures, the legal capacity of natural persons, the
authenticity of all documents submitted to me as originals, the conformity to
original documents of all documents submitted to me as duplicates or
certified or conformed copies, and the authenticity of the originals of such
latter documents.  I also have assumed that at the time of execution,
authentication, issuance and delivery of the Debt Securities and the
Guarantees, the Indenture will have been duly executed and delivered by BULI
and KeySpan and will be the valid and legally binding obligation of the
Trustee.

     Based upon the foregoing, and subject to the qualifications and
limitations stated herein, I am of the opinion that:

          1.   With respect to the Debt Securities to be issued under the
     Indenture, assuming (a) the taking of all necessary corporate action to
     approve the issuance and terms of the Debt Securities, the terms of the
     offering thereof and related matters by the Board of Directors of BULI,
     a duly constituted and acting committee of such Board or duly authorized
     officers of BULI (such Board of Directors, committee or authorized
     officers being hereinafter referred to as the "BULI Board") and (b) the
     due execution, authentication, issuance and delivery of the Debt
     Securities, upon payment of the consideration therefor provided for in
     the applicable definitive purchase, underwriting or similar agreement
     approved by the BULI Board and otherwise in accordance with the
     provisions of the Indenture and such agreement, the Debt Securities will
     constitute valid and legally binding obligations of BULI enforceable
     against BULI in accordance with their terms, except as may be limited by
     equitable principles which may limit the availability of certain
     equitable remedies (such as specific performance) in certain instances,
     and applicable bankruptcy, insolvency, fraudulent conveyance,
     reorganization, moratorium or similar laws related to or affecting
     creditors' rights generally.

          2.   With respect to the Guarantees, assuming (a) the taking of all
     necessary corporate action to approve the issuance and terms of the
     Guarantees and related matters by the Board of Directors of KeySpan, a

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     duly constituted and acting committee of such Board or duly authorized
     officers of KeySpan (such Board of Directors, committee or authorized
     officers being hereinafter referred to as the "KeySpan Board"), (b) the
     due execution, authentication, issuance and delivery of the Debt
     Securities upon payment of the consideration therefor provided for in
     the applicable definitive purchase, underwriting or similarly agreement
     approved by the BULI Board and otherwise in accordance with the
     provisions of the Indenture and such agreement and (c) the due issuance
     of the Guarantees, the Guarantees will constitute valid and legally
     binding obligations of KeySpan enforceable against KeySpan in accordance
     with their terms, except as may be limited by equitable principles which
     may limit the availability of certain equitable securities (such as
     specific performance) in certain instances and applicable bankruptcy,
     insolvency, fraudulent conveyance, reorganization, moratorium or similar
     laws related to or affecting creditors' rights generally.

     The opinions expressed above are subject to the qualification that I am
a member of the Bar of the State of New York and such opinions are limited to
the laws of the State of New York, the laws of the United States of America
and, to the extent relevant to the opinion expressed above, the Business
Corporation Law of the State of New York (and the Transportation Corporations
Law of the State of New York).

     I hereby consent to the reference to me under the caption "Legal
Opinions" in the Prospectus included in the Registration Statement and to the
filing of this opinion as Exhibit 5(a) to the Registration Statement.  The
foregoing, however, shall not constitute an admission by me that I am an
expert as provided for in Section 7 and 11 of the Act.

                                    Very truly yours,


















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