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                                                                     EXHIBIT 2.8

                              CERTIFICATE OF MERGER
                                       OF
                             JONES ACQUISITION CORP.
                                      INTO
                                H.V. JONES, INC.


      Jones Acquisition Corp., a corporation organized and existing under and by
virtue of the General Corporation Law ("GCL") of the State of Delaware,


      DOES HEREBY CERTIFY:


      FIRST:      That the name and state of incorporation of each of the
constituent corporations of the merger is as follows:


                   NAME                           STATE OF INCORPORATION
      Jones Acquisition Corp.                            Delaware
      H.V. Jones, Inc.                                    Texas

      SECOND:     That an Agreement and Plan of Merger (the "Agreement")
between the parties to the merger has been approved, adopted, certified,
executed and acknowledged by each of the constituent corporations in accordance
with the requirements of Section 252 of the GCL of the State of Delaware.


      THIRD:      That the surviving corporation of the merger is H.V.
Jones, Inc.

      FOURTH:     That the certificate of incorporation of H.V. Jones, Inc.
a Texas corporation, the surviving corporation, shall be the Certificate
of Incorporation of the surviving corporation.

      FIFTH:      That the executed Agreement is on file at the principal place
of business of the surviving corporation. The address of the principal place of
business of the surviving corporation is 1626 West Sam Houston Parkway North,
Houston, Texas, 77043.


      SIXTH:      That a copy of the Agreement will be furnished by the
surviving corporation, on request and without cost to any stockholder of
any constituent corporation.

      SEVENTH:    That, H.V. Jones, Inc. survives the merger and may be served
with process in the State of Delaware in any proceeding for enforcement of any
obligation of any constituent Delaware corporation as well as for enforcement
of any obligation of the surviving corporation arising from the merger,
including any suit or other proceeding to enforce the right of any stockholder
as determined in appraisal proceedings pursuant to the provisions of Section 262
of GCL of Delaware, and it does hereby irrevocably appoint the Secretary of
State of Delaware as its agent to accept service of process in any such suit or
other proceeding. The address to which a copy of such process shall be mailed by
the Secretary of State of Delaware is 1626 West Sam Houston Parkway North,
Houston,
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Texas, 77043 until the surviving corporation shall have hereafter designated in
writing to the said Secretary of State a different address for such purpose.

      EIGHTH:     The merger shall become effective upon the filing of
this Certificate of Merger with the State of Delaware.


      IN WITNESS WHEREOF, the parties have caused the Certificate to be
signed by Jack Leadbeater, President of Jones Acquisition Corp. and Hugh
V. Jones, President of H.V. Jones, Inc. this ______ day of March, 1998.


                                 JONES ACQUISITION CORP.


                                 By:  _________________________________
                                      Jack Leadbeater, President


                                 H.V. JONES, INC.


                                 By:  _________________________________
                                      Hugh V. Jones, President


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