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                                                                   EXHIBIT 3.7


                                     BYLAWS
                                       OF
                               EAE SERVICES, INC.


                    ARTICLE ONE: REGISTERED OFFICE AND AGENT

     1.1    REGISTER OFFICE AND AGENT. The registered office of the corporation
is located at 8052 Cypress Street, Houston, Texas, 77012. The name of the
registered agent of the corporation at such address is Frank W. Eakin.

                      ARTICLE TWO: SHAREHOLDERS' MEETINGS

     2.1    PLACE OF MEETINGS. All meetings of the shareholders shall be held at
the registered office of the corporation, or by telephone, or at such other
places within or without the State of Texas, as may be designated from time to
time by the Board of Directors.

     2.2    TIME OF ANNUAL MEETING. The annual meetings of the shareholders 
shall be held each year at ______ p.m. on the first Tuesday of April. If this
day falls on a legal holiday, the annual meeting shall be held at the same time
on the next following business day.

     2.3    NOTICE OF SHAREHOLDERS' MEETING. Written or printed notice stating
the place, day and hour of the shareholders' meeting and, in case of a special
meeting, the purpose or purposes for which the meeting is called, shall be
delivered to each shareholder entitled to vote at such meeting not less than
ten (10) days nor more than sixty (60) days before the date of the meeting,
either personally or by mail, by or at the direction of the President, the
Secretary, or the Officer or person calling the meeting, with postage thereon
prepaid, addressed to the shareholder at his address as it appears on the share
transfer records of the corporation, or that address given by the shareholder
to the corporation for the purpose of notice. Notice of adjourned meetings is
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necessary unless the meeting is adjourned for thirty (30) days or more, in which
case notice of the adjourned meeting shall be given as in the case of any
special meeting.

     2.4    SPECIAL MEETINGS. Special meetings of the shareholders for any 
purpose or purposes whatsoever may be called at any time (1) by the President,
the Board of Directors, or such other person or persons as may be authorized in
the Articles of Incorporation or the Bylaws, or (2) by the holders of at least
ten percent (10%) of all the shares entitled to vote at the proposed special
meeting, unless the Articles of Incorporation provide for a number of shares
greater than or less than ten percent (10%), in which event special meetings of
the shareholders may be called by the holders of at least the percentage of
shares so specified in the Articles of Incorporation, but in no event shall the
Article of Incorporation provide for a number of shares greater than fifty
percent (50%). The record date for determining shareholders entitled to call a
special meeting shall be the date the first shareholder signs the notice of
that meeting. Only business within the purpose or purposes described in the
notice required in Article 2.03 may be conducted at a special meeting of the
shareholders.

     2.5    QUORUM. With respect to any matter, a quorum shall be present at a
meeting of the shareholders if the holders of a majority of the shares entitled
to vote on that matter are represented at the meeting in person or by proxy.
Once a quorum is present at a meeting of shareholders, the shareholders
represented in person or by proxy at the meeting may conduct such business as
may be properly brought before the meeting until it is adjourned, and the
subsequent withdrawal from the meeting of any shareholder or the refusal of any
shareholder represented in person or by proxy shall not affect the presence of
a quorum at the meeting.


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         The shareholders represented in person or by proxy at a meeting of
shareholders at which a quorum is not present may adjourn the meeting until such
time and to such place as may be determined by vote of the holders of a majority
of the shares represented in person or by proxy at that meeting. 

         2.6    VOTING.  Only persons listed as shareholders on the share 
transfer records for shares of the corporation on the record date shall be 
entitled to notice of and to vote at any shareholder meeting. The record date 
for such determination of shareholders shall be the date on which notice of the
meeting is mailed, unless some other day is fixed by the Board of Directors for
the determination of shareholders of record. Each outstanding share, regardless
of class, shall be entitled to one vote on each matter submitted to a vote at a
meeting of the shareholders, except (a) to the extent the Articles of
Incorporation provide for more or less than one vote per share or (if and to
the extent permitted by the Texas Business Corporation Act) limit or deny
voting rights to the holders of the shares of any class or series, or (b) as
otherwise provided by the Texas Business Corporation Act. 

         With respect to any matter, other than the election of directors or a
matter for which the affirmative vote of the holders of a specified portion of
the shares entitled to vote is required by the Texas Business Corporation Act,
the affirmative vote of the holders of a majority of the shares entitled to
vote on that matter and represented in person or by proxy at a meeting of the
shareholders at which a quorum is present shall be the act of the shareholders
unless otherwise provided in the Articles of Incorporation or these Bylaws in
accordance with Article 2.28B of the Texas Business Corporation Act.
 

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     2.7    PROXIES. Any shareholder entitled to vote or execute consents may 
do so either in person or by proxy executed in writing by the shareholder. A
telegram, telex, cablegram, or similar transmission by the shareholder, shall
be treated as an execution in writing for purposes of this provision. No proxy
shall be valid after eleven (11) months from the date of its execution, unless
otherwise provided in the proxy. 

     2.8   CONSENT OF ABSENTEES. No defect in the calling or noticing of a 
shareholders' meeting will affect the validity of any action at the meeting if
a quorum was present and if each shareholder, not present in person or by
proxy, signs a written waiver of notice, consents to the holding of the
meeting, or approves the minutes of the meeting, either before or after the
meeting, and those waivers, consents, or approvals are filed with the corporate
records or made a part of the minutes of such meeting. 

     2.9   UNANIMOUS WRITTEN CONSENT IN LIEU OF MEETING.  Any action required 
by the Texas Business Corporation Act to be taken at any annual or special
meeting of the shareholders, or any action which may be taken at any annual or
special meeting of shareholders, 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 have been signed and dated by the holder or holders
of all the shares entitled to vote with respect to the action that is the
subject of the consent. Such consents are filed with the Secretary of the
corporation.

                          ARTICLE THREE: DIRECTORS

     3.1   POWERS. The powers of the corporation shall be exercised by or under 
the authority of, and the business and affairs of the corporation shall be
managed under direction of, the Board of Directors of the corporation, subject,
however, to such limitations as are imposed by law, the 


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Articles of Incorporation, or these Bylaws as to actions to be authorized or
approved by the shareholders. The Board of Directors may, by contract or
otherwise, grant general, limited, or special power and authority to the
officers and employees of the corporation to transact the general business, or
any special business, of the corporation, and may give powers of attorney to
agents of the corporation to transact any special business requiring such
authorization.

     3.2    NUMBER AND QUALIFICATION OF DIRECTORS. The authorized number of
Directors of this corporation shall be at least two (2) and not more than five
(five), as determined from time to time by the Board of Directors. The Directors
need not be shareholders of this corporation or residents of the State of Texas.
The number of Directors may be increased or decreased from time to time by
amendment to these Bylaws or in the manner provided in the Articles of
Incorporation or these Bylaws, but no decrease shall have the effect of
shortening the term of any incumbent Director. 

     3.3    ELECTION AND TERM OF OFFICE. At the first annual meeting of
shareholders and at each annual meeting thereafter, the holders of shares
entitled to vote in the election of directors shall elect directors by a
majority vote of the shares entitled to vote to hold office until the next
succeeding annual meeting. Unless removed in accordance with provisions of the
Articles of Incorporation or these Bylaws, each director shall hold office for
the term for which he is elected and until his successor shall have been
elected and qualified. 

            At each election for directors, every shareholder entitled to 
vote at such election shall have the right (a) to vote the number of shares 
owned by him for as many persons as there are directors to be elected and for 
whose election he has a right to vote, or (b) to cumulate his votes (unless 
the Articles of Incorporation expressly prohibit such) by giving one candidate 
as many votes as the

                                      

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number of directors multiplied by his shares shall equal, or by distributing
such votes on the same principal among any number of such candidates. Voting for
the election of Directors shall be by voice unless any shareholder demands a
ballot vote before the voting begins.

    3.4    VACANCIES. Any vacancy occurring in the Board of Directors after the
issuance of shares may be filled by the affirmative vote of a majority of the
remaining Directors though less than a quorum of the Board of Directors, or by
the sole remaining Director. The shareholders may elect a Director at any time
to fill any vacancy not filled by the Directors. A Director elected to fill a
vacancy shall be elected for the unexpired term of his predecessor in office.
Any directorship to be filled by reason of an increase in the number of
directors shall be filled by election at an annual or special meeting of
shareholders called for that purpose.

    3.5    REMOVAL OF DIRECTORS. At any meeting of shareholders called expressly
for that purpose any Director or the entire Board of Directors may be removed,
with or without cause, by a vote of the holders of a majority of the shares then
entitled to vote at an election of directors.

    3.6    PLACE OF MEETINGS. All meetings of the Board of Directors shall be 
held at the principal office of the corporation, or by telephone, or at such
place within or without the State of Texas as may be designated from time to
time by resolution of the Board of Directors or by written consent of all
members of the Board of Directors. 

    3.7    REGULAR MEETINGS. Regular meetings of the Board of Directors shall
be held, without call or notice, immediately following or simultaneous with each
annual meeting of the shareholders of the corporation, and at such other times
as the Directors may from time to time determine.


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   3.8    SPECIAL MEETINGS -- CALL AND NOTICE. Special meetings of the Board of
Directors for any purpose may be called at any time by the President or any
Director upon written or printed notice. Written or printed notice of a special
meeting shall state the place, day, hour, and in general terms, the purpose or
purposes of the meeting and the business to be transacted. Notice shall be
mailed, telefaxed, or personally delivered to each Director not later than two
(2) days prior to the day appointed for the special meeting. The business
transacted at the special meeting shall be confined to the purpose(s) and
business stated in the notice. Attendance of a director at a meeting shall
constitute a waiver of notice of such meeting, except where a director attends a
meeting for the express purpose of objecting to the transaction of any business
on the ground that the meeting is not lawfully called or convened. 

   3.9    QUORUM. A majority of the authorized number of Directors shall be 
necessary to constitute a quorum for the transaction of business of the Board
of Directors. The act of the majority of the Directors present at a meeting at
which a quorum is present shall be the act of the Board of Directors, unless
the act of a greater number is required by law or the Articles of Incorporation
or these Bylaws. 

   3.10   BOARD ACTION WITHOUT MEETING Any action required or permitted to be 
taken at a meeting of the Board of Directors or any committee may be taken
without a meeting if a consent in writing, setting forth the action so taken,
is signed by all the members of the Board of Directors or committee, as the
case may be. Such consent shall have the same force and effect as a unanimous
vote at a meeting, and may be stated as such in any document or instrument
filed with the Secretary of State.


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    3.11    ADJOURNMENT -- NOTICE. A quorum of the Directors may adjourn any
meeting of the Board of Directors to meet again at a stated hour on a stated
day. Notice of the time and place where an adjourned meeting will be held need
not be given to absent Directors if the time and place is fixed at the adjourned
meeting. In the absence of a quorum, the Directors present at any Directors'
meeting, either regular or special, may adjourn from time to time until the time
fixed for the next regular meeting of the Board. 

    3.12    CONDUCT OF MEETINGS. The Chief Executive Officer of the corporation,
or in the Chief Executive Officer's absence, any Director selected by the
Directors present at the meeting, shall preside at meetings of the Board of
Directors. The Secretary of the corporation or, in the Secretary's absence, any
person appointed by the presiding officer, shall act as Secretary of the Board
of Directors.

    3.13    COMPENSATION. Directors and members of any committee of the Board of
Directors may receive such compensation, if any, for their services, and such
reimbursement for expenses, as may be fixed or determined from time to time by
resolution of the Board of Directors. 

    3.14    INDEMNIFICATION OF DIRECTORS AND OFFICERS. The corporation shall
indemnify a director or an officer of the corporation against reasonable
expenses incurred by him in connection with a proceeding in which he is a named
defendant or respondent because he is or was a director or an officer of the
corporation if he has been wholly successful, on the merits or otherwise, in the
defense of the proceeding, or if a court of competent jurisdiction orders the
corporation to indemnify the director or officer because the court determines
indemnification is proper and equitable.


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                             ARTICLE FOUR: OFFICERS

     4.1.    TITLE AND APPOINTMENT. The officers of the corporation shall 
consist of a Chief Executive Officer, President and Chief Operating Officer, 
Secretary, and a Treasurer, each of whom shall be elected by a majority vote of
the Board of Directors at such time as the Board of Directors may from time to
time designate. Such other officers, including Vice Presidents, assistant
officers, and agents may be appointed by a majority vote of the Board of
Directors, as the Board of Directors shall from time to time determine
necessary. Any two (2) or more offices may be held by the same person. All
officers shall be elected by and shall hold office at the pleasure of the Board
of Directors. The Board of Directors shall fix the compensation and tenure of
all officers.

     4.2    CHIEF EXECUTIVE OFFICER/CHAIRMAN OF THE BOARD OF DIRECTORS. The
Chairman of the Board of Directors shall be the Chief Executive Officer of the
corporation and shall preside at all meetings of the shareholders and the Board
of Directors. The Chief Executive Officer shall have general supervisory
authority and power over the business and financial affairs of the corporation.

     4.3    PRESIDENT AND CHIEF OPERATING OFFICER. The President of the 
Corporation shall also be the Chief Operating Officer of the corporation. He
shall have active and general management of the business operations of the
corporation and shall see that all orders and resolutions of the Board of
Directors are carried into effect. The President and Chief Operating Officer
shall have the general powers and duties carried into effect. He shall have the
general powers and duties of supervision and management over the business
operations of the corporation. He also shall appoint and discharge all
subordinate agents and employees and fix their salaries, subject to review by
the Board of Directors, and shall designate the duties they are to perform.


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     4.4    VICE-PRESIDENT. In the event of the absence, disability, or 
termination of employment for any reason, of the President, the Vice-President
shall in his stead with the same authority, duties and responsibilities as the
President.

     4.5    SECRETARY. The Secretary shall keep the minutes of the meetings of
the Board of Directors and the minutes of the meetings of the shareholders in
appropriate books. He shall attend to the giving of all notices of the
corporation. He shall have charge of the books or records containing the names,
alphabetically arranged, of all persons who are shareholders of the corporation
and such other books and papers as the Board may direct, and shall perform all
the duties incidental to his office.

     4.6    TREASURER. The Treasurer shall have the care and custody of all of
the funds and securities of the corporation and shall see that the same are
deposited in the name of the corporation in such bank or depositories as the
Board of Directors may from time to time select. The Treasurer shall supervise
and direct all bookkeeping and accounting personnel and functions and shall have
the authority and power to hire and dismiss any bookkeeping or accounting
personnel.

     4.7    ASSISTANTS. Assistant secretaries or treasurers shall have such 
duties as may be delegated to them by the secretary and treasurer, respectively.

     4.8    TERM OF OFFICE. The officers of the corporation shall hold office 
until their successors are chosen and qualify in their stead. Any officer or
agent or member of a committee elected or appointed by the Board of Directors
may be removed at any time by the affirmative vote of a majority of the Board of
Directors, whenever in its judgment the best interests of the corporation will
be served thereby, but such removal shall be without prejudice to the contract


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rights, if any, of the person so removed. If any office becomes vacant for any
reason, the vacancy shall be filled by the affirmative vote of a majority of the
Board of Directors.

     4.9   DELEGATION OF DUTIES AND AUTHORITY. In the case of the absence of any
officer of the Corporation, or for any other reason that the Board may deem
sufficient as to any officer, the Board may delegate, for the time being, the
powers or duties, or any of them, of such officer to any other officer, or to
any director, provided a majority of the entire Board concurs therein.

                     ARTICLE FIVE: EXECUTION OF INSTRUMENTS

     5.1   The Board of Directors may, in its discretion, authorize an officer 
or officers, or other person or persons, to execute any corporate instrument or
document, or to sign the corporate name without limitation, except where
otherwise provided by law, and such execution or signature shall be binding on
the corporation. 

                  ARTICLE SIX: ISSUANCE AND TRANSFER OF SHARES

     6.1   REQUIREMENT OF PAYMENT FOR SHARES. The corporation may issue the 
number of shares stated in the Articles of Incorporation. Certificates for 
shares of the corporation may not be issued until the full amount of the
consideration for the shares, fixed as provided by law, has been paid. When
such consideration shall have been paid to the corporation, the shares shall be
deemed to have been issued and shall be considered fully paid and
non-assessable.

     6.2   CERTIFICATES REPRESENTING SHARES. The corporation shall deliver
certificates representing shares to which shareholders are entitled. The
certificates shall be in such form as the Board of Directors may provide. The
certificates shall be signed by the President or Vice-President and the
Secretary-Treasurer, and may be sealed with the seal of the corporation or a


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facsimile thereof. The signatures of such officers may be facsimiles, if the
certificates are to be countersigned by a transfer agent or registered by a
registrar. 

     Each certificate representing shares of the corporation shall state upon
the fact thereof: (1) that the corporation is organized under the laws of the
State of Texas, (2) the name of the person to whom issued, (3) the number and
class of shares and the designation of the series, if any, which such
certificate represents, and (4) the par value of each share represented by such
certificate, or a statement that the shares are without par value.

     6.3    REPLACEMENT OF CERTIFICATES. No new certificate representing shares
of the corporation shall be issued until the former certificate for the shares
represented thereby shall have been surrendered and canceled, except in the
case of lost or destroyed certificates in which case the Board of Directors may
order new certificates to be issued upon such terms, conditions, and guarantees
as the Board may deem necessary to impose, including the filing of sufficient
indemnity.

     6.4    TRANSFER OF SHARES. The shares and other securities of the 
corporation shall be personal property for all purposes and shall be
transferrable in accordance with the provisions of Chapter 8 -- Investment
Securities -- of the Texas Business and Commerce Code, as amended, except as
otherwise provided in the Texas Business Corporation Act. The shares may be
transferred by endorsement, by signature of the owner or the owner's agent,
attorney or legal representative, or by the delivery of the certificate. The
transferee in any transfer of shares shall be deemed to have full notice of,
and to consent to, the Bylaws of the corporation to the same extent as if the
transferee had signed a written assent thereto.


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     6.5     RESTRICTIVE ENDORSEMENT. If a restriction on the transfer, or 
registration of the transfer, of shares is imposed or agreed to by the
corporation, as permitted by the Texas Business Corporation Act, each
certificate representing shares so restricted: (1) shall conspicuously set forth
a full or summary statement of the restriction on the face of the certificate,
or (2) shall set forth such statement on the back of the certificate and
conspicuously refer to the same on the face of the certificate, or (3) shall
conspicuously state on the face or back of the certificate that such a
restriction exists pursuant to a specified document and (a) that the corporation
will furnish to the record holder of the certificate without charge upon written
request to the corporation at its principal place of business or registered
office a copy of the specified document, or (b) if such document is one required
or permitted to be and has been filed under the Texas Business Corporation Act,
that such specified document is on file in the office of the Secretary of State
and contains a full statement of such restriction.

     6.6     RIGHTS TO PURCHASE STOCK OF A SHAREHOLDER. 

             (a) When a shareholder elects to sell his shares of stock in the
corporation, the right to purchase such shares shall first be made available to
EAE Services, Inc., on the same terms made available or offered to any other
purchaser for a period of twenty (20) days, and thereafter offered for an
additional period of ten (10) days to the shareholders of the corporation, pro
rata, among the electing shareholders. 

             (b) In the event of the death of a shareholder, any successor in 
interest to the deceased shareholder's stock shall take such stock subject to
the provisions of Paragraph 6.06(a) above.


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     6.7     SALES AND OTHER TRANSFERS OF STOCK.

             (a) Shareholder Agreements. The shareholders of this corporation 
may make agreements between or among themselves through a written shareholders'
agreement, governing the purchase, among themselves, of the stock of this
corporation in the event of the death, bankruptcy, retirement, or disability of
any shareholder, and in the event of a transfer by a shareholder of his stock by
donation to the shareholder's spouse and lineal descendants. A copy of any such
agreement shall be placed on file by the corporation at its principal place of
business or its registered office and shall be subject to the same right of
examination by a shareholder of the corporation, in person or by agent, attorney
or accountant, as are the books and records of the corporation. The provisions
of any such agreement shall be binding upon the parties to the agreement and
their respective heirs, administrators, legatees, executors and assigns. 

             (b) Stock Redemption Agreements. The corporation and any number of
the shareholders of the corporation may enter into stock redemption agreements.
A copy of any such agreement shall be placed on file by the corporation at its
principal place of business or its registered office.

                      ARTICLE SEVEN: RECORD AND REPORTS

     7.1     BOOKS AND RECORDS. The corporation shall keep books and records of
account, and shall keep minutes of the proceedings of its shareholders, its
Board of Directors, and each committee of its Board of Directors. The
corporation shall keep at its registered office or its principal place of
business, or at the office of its transfer agent or registrar, a record of the
original issuance of shares issued by the corporation and a record of each
transfer of those shares that have been presented to the corporation for
registration of transfer. Such records shall contain the names


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and addresses of all past and current shareholders of the corporation and the 
number and class of shares issued by the corporation held by each of them.

     7.2     EXAMINATION OF BOOKS AND RECORDS. Any person who shall have been a
shareholder for at least six (6) months immediately preceding his demand, or
shall be the holder of at least five percent (5%) of all outstanding shares of
the corporation, upon written demand stating the purpose thereof, shall have the
right to examine, in person or by agent, accountant, or attorney, at any
reasonable time or times, for any proper purpose, its relevant books and records
of account, minutes, and share transfer records, and to make extracts therefrom.
A director may examine the corporation's books and records of account, share
transfer records, corporate minutes and any other corporate books and records
for any purpose reasonably related to the director's service as a director.

                       ARTICLE EIGHT: FIXING RECORD DATES

     8.1     FIXING RECORD DATE. For the purpose of determining shareholders
entitled to notice of or to vote at any meeting of shareholders or any
adjournment thereof, or entitled to receive a distribution by the corporation
(other than a distribution involving a purchase or redemption by the corporation
of any of its own shares) or a share dividend, or in order to make a 
determination of shareholders for any other proper purpose (other than
determining shareholders entitled to consent to action by shareholders proposed
to be taken without a meeting of shareholders), the Board of Directors may
provide that the share transfer records shall be closed for a stated period but
not to exceed, in any case, sixty (60) days. If the share transfer records shall
be closed for the purpose of determining shareholders entitled to notice of or
to vote at a meeting of shareholders, such records shall be closed for at least
ten (10) days immediately preceding such meeting.


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                      ARTICLE NINE: AMENDMENT OF BYLAWS

     9.1   AMENDMENT OF BYLAWS. The power to alter, amend, or repeal these 
Bylaws is vested in the Board of Directors of the corporation, subject to
repeal, change or amendment by the shareholders of the corporation.

     The foregoing Bylaws of EAE Services, Inc., are unanimously adopted as the
Bylaws of EAE Services, Inc. by the Board of Directors of EAE Services, Inc., on
this 20th day of July, 1997.

                                       DIRECTORS:


                                       /s/ Samuel F. Eakin
                                       ---------------------------
                                       Samuel F. Eakin, Director

                                       

                                       /s/ David B. Ammons
                                       -------------------------- 
                                       David B. Ammons, Director


Attest: /s/ David B. Ammons        
       -------------------------------
            David B. Ammons, Secretary

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