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                                                                      EXHIBIT 3B

                        CONSOLIDATED NATURAL GAS COMPANY

                                     BYLAWS

                           AS AMENDED JANUARY 28, 2000


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                                TABLE OF CONTENTS

ARTICLE I
STOCKHOLDERS...................................................................1
    1.1  Annual Meetings.......................................................1
    1.2  Special Meetings......................................................1
    1.3  Notice of Meetings....................................................1
    1.4  Adjournments..........................................................1
    1.5  Quorum................................................................1
    1.6  Organization..........................................................2
    1.7  Voting; Proxies.......................................................2
    1.8  Fixing Date for Determination of Stockholders of Record...............3
    1.9  List of Stockholders Entitled to Vote.................................4
    1.10  Consent of Stockholders in Lieu of Meeting...........................4

ARTICLE II
BOARD OF DIRECTORS.............................................................5
    2.1  Functions and Compensation............................................5
    2.2  Number; Qualifications................................................5
    2.3  Election; Resignation; Removal; Vacancies.............................5
    2.4  Regular Meetings......................................................5
    2.5  Special Meetings......................................................5
    2.6  Telephonic Meetings Permitted.........................................5
    2.7  Quorum; Vote Required for Action......................................5
    2.8  Organization..........................................................6
    2.9  Action by Directors Without a Meeting.................................6

ARTICLE III
OFFICERS...................................................................... 6
    3.1  Executive Officers; Election; Qualifications..........................6
    3.2  Term of Office; Resignation; Removal; Vacancies.......................6
    3.3  Powers and Duties of Executive Officers...............................6
    3.4  Compensation..........................................................6

ARTICLE IV
STOCK..........................................................................7
    4.1  Certificates..........................................................7
    4.2  Transfer of Stock.....................................................7
    4.3  Lost, Stolen or Destroyed Stock Certificates; Issuance of New
         Certificates..........................................................7

ARTICLE V
MISCELLANEOUS..................................................................7
    5.1  Fiscal Year...........................................................7
    5.2  Seal..................................................................7
    5.3  Waiver of Notice of Meetings of Stockholders, Directors and
         Committees............................................................7
    5.4  Interested Directors; Quorum..........................................8
    5.5  Form of Records.......................................................8
    5.6  Amendment of Bylaws...................................................8

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                                    ARTICLE I
                                  STOCKHOLDERS

         1.1 ANNUAL MEETINGS. An annual meeting of the stockholders shall be
held for the election of directors on the third Tuesday in May of each year or
on such other date and at such time and place, either within or without the
State of Delaware, as may be designated by resolution of the Board of Directors
from time to time. Any other proper business may be transacted at the annual
meeting.

         1.2 SPECIAL MEETINGS. Special meetings of stockholders for any purpose
or purposes may be called at any time by the Chairman of the Board, if any, the
President or the Board of Directors. Such special meetings shall be held at such
date, time and place either within or without the State of Delaware as may be
stated in the notice of the meeting.

         1.3 NOTICE OF MEETINGS. Whenever stockholders are required or permitted
to take any action at a meeting, a written notice of the meeting shall be given
which shall state the place, date and hour of the meeting, and, in the case of a
special meeting, the purpose or purposes for which the meeting is called. Unless
otherwise provided by law, the written notice of any meeting shall be given not
less than ten nor more than sixty days before the date of the meeting to each
stockholder entitled to vote at such meeting. If mailed, such notice shall be
deemed to be given when deposited in the mail, postage prepaid, directed to the
stockholder at his address as it appears on the records of the Company.

         1.4 ADJOURNMENTS. Any meeting of stockholders, annual or special, may
adjourn from time to time to reconvene at the same or some other place, and
notice need not be given of any such adjourned meeting if the time and place
thereof are announced at the meeting at which the adjournment is taken. At the
adjourned meeting the Company may transact any business which might have been
transacted at the original meeting. If the adjournment is for more than thirty
days, or if after the adjournment a new record date is fixed for the adjourned
meeting, a notice of the adjourned meeting shall be given to each stockholder of
record entitled to vote at the meeting.

         1.5 QUORUM. At each meeting of stockholders, except where otherwise
provided by law or the Certificate of Incorporation or these Bylaws, the holders
of a majority of the outstanding shares of stock entitled to vote at the
meeting, present in person or by proxy, shall constitute a quorum. For purposes
of the foregoing, two or more classes or series of stock shall be considered a
single class if the holders thereof are entitled to vote together as a single
class at the meeting. In the absence of a quorum, the stockholders so present
may, by majority vote, adjourn the meeting from time to time in the manner
provided in Section 1.4 of these Bylaws until a quorum shall attend. Shares of
its own stock belonging to the Company or to another corporation, if a majority
of the shares entitled to vote in the election of directors of such other
corporation is held, directly or indirectly, by the Company, shall neither be
entitled to vote nor be counted for quorum purposes; provided, however, that the
foregoing shall not limit the right of any corporation to vote stock, including
but not limited to its own stock, held by it in a fiduciary capacity.

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         1.6 ORGANIZATION. Meetings of stockholders shall be presided over by
the Chairman of the Board, if any, or in his absence by the President, or in his
absence by a Vice President, or in the absence of the foregoing persons by a
chairman designated by the Board of Directors, or in the absence of such
designation, by a chairman chosen at the meeting. The Secretary shall act as
secretary of the meeting, but in his absence the chairman of the meeting may
appoint any person to act as secretary of the meeting.

         1.7 VOTING; PROXIES. (a) Unless otherwise provided in the Certificate
of Incorporation, each stockholder entitled to vote at any meeting of
stockholders shall be entitled to one vote for each share of stock held by him
which has voting power upon the matter in question.

         (b) Each stockholder entitled to vote at a meeting of stockholders or
to express consent or dissent to corporate action in writing without a meeting
may authorize another person or persons to act for him by proxy, but no such
proxy shall be voted or acted upon after three years from its date, unless the
proxy provides for a longer period.

         (c) Without limiting the manner in which a stockholder may authorize
another person or persons to act for him as proxy pursuant to this subsection
(b) of this Section, the following shall constitute a valid means by which a
stockholder may grant such authority:

                  (1) A stockholder may execute a writing authorizing another
         person or persons to act for him as proxy. Execution may be
         accomplished by the stockholder or his authorized officer, director,
         employee or agent signing such writing or causing his or her signature
         to be affixed to such writing by any reasonable means including, but
         not limited to, by facsimile signature.

                  (2) A stockholder may authorize another person or persons to
         act for him as proxy by transmitting or authorizing the transmission of
         a telegram, cablegram or other means of electronic transmission to the
         person who will be the holder of the proxy or to a proxy solicitation
         firm, proxy support service organization or like agent duly authorized
         by the person who will be the holder of the proxy to receive such
         transmission, provided that any such telegram, cablegram or other means
         of electronic transmission must either set forth or be submitted with
         information from which it can be determined that the telegram,
         cablegram, or other electronic transmission was authorized by the
         stockholder. If it is determined that such telegrams, cablegrams or
         other electronic transmissions are valid, the inspectors or, if there
         are no inspectors, such other persons making that determination shall
         specify the information upon which they relied.

         (d) Any copy, facsimile, telecommunication or other reliable
reproduction of the writing or transmission created pursuant to this subsection
(c) of this Section, may be submitted or used in lieu of the original writing or
transmission for any and all purposes for which the original writing or
transmission could be used, provided that such copy, facsimile,
telecommunication or other reproduction shall be a complete reproduction of the
entire original writing or transmission.

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         (e) A duly executed proxy shall be irrevocable if it states that it is
irrevocable and if, and only as long as, it is coupled with an interest
sufficient in law to support an irrevocable power. A proxy may be made
irrevocable regardless of whether the interest with which it is coupled is an
interest in the stock itself or an interest in the Company generally. A
stockholder may revoke any proxy which is not irrevocable by attending the
meeting and voting in person or by filing an instrument in writing revoking the
proxy or another duly executed proxy bearing a later date with the Secretary of
the Company. Voting at meetings of stockholders need not be by written ballot
and need not be conducted by inspectors unless the holders of a majority of the
outstanding shares of all classes of stock entitled to vote thereon present in
person or by proxy at such meeting shall so determine. At all meetings of
stockholders for the election of directors, a plurality of the votes cast shall
be sufficient to elect. All other elections and questions shall, unless
otherwise provided by law or by the Certificate of Incorporation or these
Bylaws, be decided by the vote of the holders of a majority of the outstanding
shares of stock entitled to vote thereon present in person or by proxy at the
meeting, provided that (except as otherwise required by law or by the
Certificate of Incorporation) the Board of Directors may require a larger vote
upon any election or question.

         1.8 FIXING DATE FOR DETERMINATION OF STOCKHOLDERS OF RECORD.

         (a) Notice and Voting Rights: In order that the Company may determine
the stockholders entitled to notice of or to vote at any meeting of stockholders
or any adjournment thereof, the Board of Directors may fix a record date, which
record date shall not precede the date upon which the resolution fixing the
record date is adopted by the Board of Directors, and which record date shall
not be more than sixty nor less than ten days before the date of such meeting.
If no record date is fixed by the Board of Directors, the record date for
determining stockholders entitled to notice of or to vote at a meeting of
stockholders shall be at the close of business on the day next preceding the day
on which notice is given, or, if notice is waived, at the close of business on
the day next preceding the day on which the meeting is held. A determination of
stockholders of record entitled to notice of or to vote at a meeting of
stockholders shall apply to any adjournment of the meeting; provided, however,
that the Board of Directors may fix a new record date for the adjourned meeting.

         (b) Consents: In order that the Company may determine the stockholders
entitled to consent to corporate action in writing without a meeting, the Board
of Directors may fix a record date, which record date shall not precede the date
upon which the resolution fixing the record date is adopted by the Board of
Directors, and which date shall not be more than ten days after the date upon
which the resolution fixing the record date is adopted by the Board of
Directors. If no record date has been fixed by the Board of Directors, the
record date for determining stockholders entitled to consent to corporate action
in writing without a meeting, when no prior action by the Board of Directors is
required by law, the Certificate of Incorporation or these Bylaws, shall be the
first date on which a signed written consent setting forth the action taken or
proposed to be taken is delivered to the Company by delivery to its registered
office, principal place of business, or an officer or agent of the Company
having custody of the book in which proceedings of meetings of stockholders are
recorded. Delivery made to the Company's registered office shall be by hand or
by certified mail, return receipt requested. If no record date has been fixed by
the Board of Directors and prior action by the Board of Directors is required by
law, the Certificate of Incorporation or these Bylaws, the

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record date for determining stockholders entitled to consent to corporate action
in writing without a meeting shall be at the close of business on the day on
which the Board of Directors adopts the resolution taking such prior action.

         (c) Other Lawful Action: In order that the Company may determine the
stockholders entitled to receive payment of any dividend or other distribution
or allotment of any rights or the stockholders entitled to exercise any rights
in respect of any change, conversion or exchange of stock, or for the purpose of
any other lawful action, the Board of Directors may fix a record date, which
record date shall not precede the date upon which the resolution fixing the
record date is adopted, and which record date shall be not more than sixty days
prior to such action. If no record date is fixed, the record date for
determining stockholders for any such purpose shall be at the close of business
on the day on which the Board of Directors adopts the resolution relating
thereto.

         1.9 LIST OF STOCKHOLDERS ENTITLED TO VOTE. The Secretary shall prepare
and make, at least ten days before every meeting of stockholders, a complete
list of the stockholders entitled to vote at the meeting, arranged in
alphabetical order, and showing the address of each stockholder and the number
of shares registered in the name of each stockholder. Such list shall be open to
the examination of any stockholder, for any purpose germane to the meeting,
during ordinary business hours, for a period of at least ten days prior to the
meeting, either at a place within the city where the meeting is to be held,
which place shall be specified in the notice of the meeting, or, if not so
specified, at the place where the meeting is to be held. The list shall also be
produced and kept at the time and place of the meeting during the whole time
thereof, and may be inspected by any stockholder who is present.

         1.10 CONSENT OF STOCKHOLDERS IN LIEU OF MEETING. Unless otherwise
restricted by the Certificate of Incorporation, any action required or permitted
to be taken at any annual or special meeting of the stockholders may be taken
without a meeting, without prior notice and without a vote, if a consent or
consents in writing, setting forth the action so taken, shall be signed by the
holders of outstanding stock having not less than the minimum number of votes
that would be necessary to authorize or take such action at a meeting at which
all shares entitled to vote thereon were present and voted. The consent or
consents shall be delivered to the Company by delivery to its registered office,
principal place of business, or an officer or agent of the Company having
custody of the book in which proceedings of meetings of stockholders are
recorded. Delivery made to the Company's registered office shall be by hand or
by certified or registered mail, return receipt requested. Every written consent
shall bear the date of signature of each stockholder who signs the consent and
no written consent shall be effective to take the corporate action referred to
therein unless, within sixty days of the earliest dated consent delivered in the
manner required by law, to the Company, written consents signed by a sufficient
number of holders to take action are delivered to the Company in the manner
indicated above. Prompt notice of the taking of the corporate action without a
meeting by less than unanimous written consent shall be given to those
stockholders who have not consented in writing.

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                                   ARTICLE II
                               BOARD OF DIRECTORS

         2.1 FUNCTIONS AND COMPENSATION. The business and affairs of the Company
shall be managed by or under the direction of the Board of Directors of the
Company. The Board of Directors shall have the authority to fix the compensation
of the members thereof.

         2.2 NUMBER; QUALIFICATIONS. The Board of Directors shall consist of one
or more members, the number thereof to be determined from time to time by
resolution of the Board of Directors. Directors need not be stockholders.

         2.3 ELECTION; RESIGNATION; REMOVAL; VACANCIES. The Board of Directors
shall initially consist of the persons elected as such by the incorporator. At
the first annual meeting of stockholders and at each annual meeting thereafter,
the stockholders shall elect Directors to replace those Directors whose terms
then expire. Any Director may resign at any time upon written notice to the
Company. Stockholders may remove Directors with or without cause by vote of a
majority of the shares then entitled to vote at an election of directors. Any
vacancy occurring in the Board of Directors for any cause may be filled by a
majority of the remaining members of the Board of Directors, although such
majority is less than a quorum, or by a plurality of the votes cast at a meeting
of stockholders, and each Director so elected shall hold office until the
expiration of the term of office of the Director whom he has replaced.

         2.4 REGULAR MEETINGS. Regular meetings of the Board of Directors may be
held at such places within or without the State of Delaware and at such times as
the Board of Directors may from time to time determine, and if so determined
notices thereof need not be given.

         2.5 SPECIAL MEETINGS. Special meetings of the Board of Directors may be
held at any time or place within or without the State of Delaware whenever
called by the Chairman of the Board, the President, any Vice President, the
Secretary, or by a plurality of directors in office. Reasonable notice thereof
shall be given by the person or persons calling the meeting, not later than the
second day before the date of the special meeting.

         2.6 TELEPHONIC MEETINGS PERMITTED. Members of the Board of Directors
may participate in a meeting by means of conference telephone or similar
communications equipment by means of which all persons participating in the
meeting can hear each other, and participation in a meeting pursuant to this
Section 2.6 shall constitute presence in person at such meeting.

         2.7 QUORUM; VOTE REQUIRED FOR ACTION. At all meetings of the Board of
Directors a majority of the entire Board shall constitute a quorum for the
transaction of business. Except in cases in which the Certificate of
Incorporation or these Bylaws otherwise provide, the vote of a majority of the
directors present at a meeting at which a quorum is present shall be the act of
the Board of Directors.

         2.8 ORGANIZATION. Meetings of the Board of Directors shall be presided
over by the Chairman of the Board, if any, or in his or her absence by the
President, or in his or her absence by a

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chairman chosen at the meeting. The Secretary shall act as secretary of the
meeting, but in his or her absence the chairman of the meeting may appoint any
person to act as secretary of the meeting.

         2.9 ACTION BY DIRECTORS WITHOUT A MEETING. Unless otherwise restricted
by the Certificate of Incorporation or these Bylaws, any action required or
permitted to be taken at any meeting of the Board of Directors may be taken
without a meeting if all members of the Board consent thereto in writing, and
the writing or writings are filed with the minutes of proceedings of the Board.

                                   ARTICLE III
                                    OFFICERS

         3.1 EXECUTIVE OFFICERS; ELECTION; QUALIFICATIONS. As soon as
practicable after the annual meeting of stockholders in each year the Board of
Directors shall elect a President and Secretary, and it may, if it so
determines, elect a Chairman of the Board. The Board of Directors may also elect
one or more Vice Presidents, one or more Assistant Vice Presidents, one or more
Assistant Secretaries, a Treasurer and one or more Assistant Treasurers and may
give any of them such further designations or alternate titles as it considers
desirable. Any number of offices may be held by the same person.

         3.2 TERM OF OFFICE; RESIGNATION; REMOVAL; VACANCIES. Except as
otherwise provided in the resolution of the Board of Directors electing any
officer, each such officer shall hold office until the first meeting of the
Board of Directors after the annual meeting of stockholders next succeeding this
election, and until his successor is elected and qualified or until his earlier
resignation or removal. Any officer may resign at any time upon written notice
to the Company. The Board of Directors may remove any officer with or without
cause at any time, but such removal shall be without prejudice to the
contractual rights of such officer, if any, with the Company. Any vacancy
occurring in any office of the Company by death, resignation, removal or
otherwise may be filled for the unexpired portion of the term by the Board of
Directors at any regular or special meeting.

         3.3 POWERS AND DUTIES OF EXECUTIVE OFFICERS. The officers of the
Company shall have such powers and duties in the management of the Company as
may be prescribed by the Board of Directors and, to the extent not so provided,
as generally pertain to their respective offices, subject to the control of the
Board of Directors. The Secretary shall have the duty to record the proceedings
of the meetings of the stockholders, the Board of Directors in a book to be kept
for that purpose. The Board of Directors may require any officer, agent or
employee to give security for the faithful performance of his duties.

         3.4 COMPENSATION. The Board of Directors shall fix the compensation of
the Chairman of the Board and of the President and shall fix, or authorize the
Chairman of the Board or the President to fix, the compensation of any or all
others. The Board of Directors may vote compensation to any director for
attendance at meetings or for any special services.

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                                   ARTICLE IV
                                      STOCK

         4.1 CERTIFICATES. Every holder of stock shall be entitled to have a
certificate signed by or in the name of the Company by the Chairman of the Board
of Directors, if any, or the President or a Vice President, and by the Treasurer
or an Assistant Treasurer, or the Secretary or an Assistant Secretary, of the
Company, certifying the number of shares owned by him in the Company. Any of or
all the signatures on the certificate may be a facsimile. In case any officer,
transfer agent, or registrar who has signed or whose facsimile signature has
been placed upon a certificate shall have ceased to be such officer, transfer
agent, or registrar before such certificate is issued, it may be issued by the
Company with the same effect as if he were such officer, transfer agent, or
registrar at the date of issue.

         4.2 TRANSFER OF STOCK. Upon surrender to the Company or the transfer
agent of the Company of a certificate for shares endorsed or accompanied by a
written assignment signed by the holder of record or by his duly authorized
attorney-in-fact, it shall be the duty of the Company, or its duly appointed
transfer agent, to issue a new certificate to the person entitled thereto,
cancel the old certificate and record the transaction upon its books.

         4.3 LOST, STOLEN OR DESTROYED STOCK CERTIFICATES; ISSUANCE OF NEW
CERTIFICATES. The Company may issue a new certificate of stock in the place of
any certificate theretofore issued by it, alleged to have been lost, stolen or
destroyed, and the Company may require the owner of the lost, stolen or
destroyed certificate, or his legal representative, to give the Company a bond
sufficient to indemnify it against any claim that may be made against it on
account of the alleged loss, theft or destruction of any such certificate or the
issuance of such new certificate.

                                    ARTICLE V
                                  MISCELLANEOUS

         5.1 FISCAL YEAR. The fiscal year of the Company shall be determined by
resolution of the Board of Directors.

         5.2 SEAL. The Corporate seal shall have the name of the Company
inscribed thereon and shall be in such form as may be approved from time to time
by the Board of Directors.

         5.3 WAIVER OF NOTICE OF MEETINGS OF STOCKHOLDERS, DIRECTORS AND
COMMITTEES. Any written waiver of notice, signed by the person entitled to
notice, whether before or after the time stated therein, shall be deemed
equivalent to notice. Attendance of a person at a meeting shall constitute a
waiver of notice of such meeting, except when the person attends a meeting for
the express purpose of objecting, at the beginning of the meeting, to the
transaction of any business because the meeting is not lawfully called or
convened. Neither the business to be transacted at, nor the purpose of any
regular or special meeting of the stockholders or directors need be specified in
any written waiver of notice.

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         5.4 INTERESTED DIRECTORS; QUORUM. No contract or transaction between
the Company and one or more of its directors or officers, or between the Company
and any other corporation, partnership, association, or other organization in
which one or more of its directors or officers are directors or officers, or
have a financial interest, shall be void or voidable solely for this reason, or
solely because the director or officer is present at or participates in the
meeting of the Board which authorizes the contract or transaction, or solely
because his or their votes are counted for such purpose, if: (1) the material
facts as to his relationship or interest and as to the contract or transaction
are disclosed or are known to the Board of Directors, and the Board in good
faith authorized the contract or transaction by the affirmative votes of a
majority of the disinterested directors, even though the disinterested directors
be less than a quorum; or (2) the material facts as to his relationship or
interest and as to the contract or transaction are disclosed or are known to the
stockholders entitled to vote thereon, and the contract or transaction is
specifically approved in good faith by vote of the stockholders; or (3) the
contract or transaction is fair as to the Company as of the time it is
authorized, approved or ratified, by the Board of Directors or the stockholders.
Common or interested directors may be counted in determining the presence of a
quorum at a meeting of the Board of Directors or of a committee which authorizes
the contract or transaction.

         5.5 FORM OF RECORDS. Any records maintained by the Company in the
regular course of its business, including its stock ledger, books of account,
and minute books, may be kept on, or be in the form of, punch cards, magnetic
tape, photographs, microphotographs, or any other information storage device,
provided that the records so kept can be converted into clearly legible form
within a reasonable time. The Company shall so convert any records so kept upon
the request of any person entitled to inspect the same.

         5.6 AMENDMENT OF BYLAWS. These Bylaws may be altered or repealed, and
new bylaws made, by the Board of Directors, but the stockholders may make
additional bylaws and may alter and repeal any bylaws whether adopted by them or
otherwise.

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