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     demands, costs, penalties, attorneys' fees and liabilities arising
     as a result of Company's failure to do so.

12.  Effect of Prior Agreements:  This Agreement contains the entire
     understanding between the parties hereto and supersedes any prior
     employment agreement between the Company or any predecessor of the Company
     and the Executive, except that this Agreement shall not affect or operate
     to reduce or increase any benefit or compensation inuring to the Executive
     the amount payable to the Executive under Paragraph 5.B of the Employment
     Agreement.

13.  Enforceability and Governing Law:  Should any portion of this Agreement be
     held unenforceable or inoperative for any reason, in whole or in part, it
     shall not affect any other portion of this Agreement, but the remainder
     shall be effective as though the ineffective portion is not contained
     herein.  The Executive shall not assign or transfer his rights or duties
     under this Agreement without the prior written consent of the Company.  No
     waiver or any breach or violations of this Agreement by the parties shall
     be deemed made unless made in writing.  Any such waiver shall not operate
     or be construed as a waiver of any subsequent breach or violation of this
     Agreement.  This Agreement is to be effective in and shall be construed in
     accordance with the laws of the State of Texas.  This Agreement is binding
     upon and shall inure to the benefit of the parties hereto and their
     successors and assigns.  This Agreement contains the entire understanding
     of the parties.

14.  General Provisions:

     a.   Non-Assignability:  Neither this Agreement nor any right or interest
          hereunder shall be assignable by the Executive, his beneficiaries or
          legal representatives without the Company's prior written consent;
          provided, however, nothing in this Paragraph 12.A shall preclude (i)
          the Executive from designating a beneficiary to receive any benefit
          payable hereunder upon his death or (ii) the executors, administrators
          or other legal representatives of the Executive or his estate from
          assigning any rights hereunder to the person or persons entitled
          thereto.

     b.   No Attachment:  Except as required by law, no right to receive
          payments under this Agreement shall be subject to anticipation,
          commutation, alienation, sale, assignment, encumbrance, charge,
          pledge, hypothecation, execution, attachment, levy or similar process
          or assignment by operation of law, and any attempt, voluntary or
          involuntary, to effect such action shall be null, void and of no
          effect.

     c.   Binding Effect:  This Agreement shall be binding upon and inure to the
          benefit of the Company, its successors and assigns, except as
          otherwise provided herein.

     d.   Modification and Waiver:

          (i)  Amendment of Agreement:  This Agreement may not be modified or

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