EXHIBIT 4.2


                             CERTIFICATE OF MERGER
                                      OF
                SYNTROLEUM CORPORATION, AN OKLAHOMA CORPORATION
                                     INTO
                     SLH CORPORATION, A KANSAS CORPORATION

        (PURSUANT TO SECTION 17-6702 OF THE KANSAS GENERAL CORPORATION
        CODE AND SECTION 1082 OF THE OKLAHOMA GENERAL CORPORATION ACT)

        Pursuant to the provisions of the Kansas General Corporation Code and 
the Oklahoma General Corporation Act, the undersigned corporation certifies as 
follows:

        1.  The constituent corporations to the merger are SLH Corporation, a 
Kansas corporation, and Syntroleum Corporation, an Oklahoma corporation.

        2.  SLH Corporation and Syntroleum Corporation have entered into an 
Agreement and Plan of Merger and Reorganization, dated as of March 30, 1998 (the
"Merger Agreement"), which has been approved, adopted, certified, executed and 
acknowledged by SLH Corporation and Syntroleum Corporation in accordance with 
Section 17-6702 of the Kansas General Corporation Code and Section 1082 of the 
Oklahoma General Corporation Act.

        3. The name of the surviving corporation is SLH Corporation.

        4.  The Articles of Incorporation of the surviving corporation shall be 
SLH Corporation's Articles of Incorporation with the following amendments:

             (a)  Article I shall be amended to change the name of the 
                  corporation to Syntroleum Corporation, as follows:


                                   ARTICLE I
                                     NAME

             The name of the corporation (which is hereinafter referred to as
the "Corporation") is:

                            SYNTROLEUM CORPORATION

             (b)  The first paragraph of Article IV shall be amended (i) to
                  increase the authorized shares of Common Stock, par value
                  $0.01 per share, from Thirty

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                  Million shares to One Hundred Fifty Million shares and (ii) to
                  increase the authorized shares of Preferred Stock, par value
                  $0.01 per share, from One Million shares to Five Million
                  shares, as follows:

                                  ARTICLE IV

                                 Capital Stock

            The total number of shares of stock which the Corporation shall have
        authority to issue is One Hundred Fifty Five Million (155,000,000),
        consisting of Five Million (5,000,000) shares of Preferred Stock, par
        value $0.01 per share (hereinafter referred to as "Preferred Stock"),
        and One Hundred Million (150,000,000) shares of Common Stock, par value
        $0.01 per share (hereinafter referred to as "Common Stock").

        5.  The executed Merger Agreement is on file at the office of the 
surviving corporation located at 1350 South Boulder, Suite 1100, Tulsa, Oklahoma
74119.

        6.  A copy of the Merger Agreement will be furnished by the surviving 
corporation, on request and without cost, to any stockholder of SLH Corporation 
or Syntroleum Corporation.

        7.  The authorized capital stock of Syntroleum Corporation, the only 
constituent corporation to the merger which is not a Kansas corporation, is as 
follows:

            Common Stock, par value $.001 per share - 50,000,000 shares
            Preferred Stock, par value $0.01 per share - 1,000,000 shares

        8.  SLH Corporation hereby agrees that it may be served with process in
Oklahoma in any proceeding for enforcement of any obligation of Syntroleum 
Corporation, as well as for enforcement of any obligation of SLH Corporation 
arising from the merger, including any suit or other proceeding to enforce the 
right of any stockholders as determined in appraisal proceedings pursuant to 
Section 1091 of the Oklahoma General Corporation Act and SLH Corporation hereby 
irrevocably appoints the Secretary of State of the State of Oklahoma as its 
agent to accept service of process in any such suit or other proceedings and a 
copy of such process shall be mailed by the Secretary of State to SLH 
Corporation at the following address:

            1350 South Boulder, Suite 1100
            Tulsa, Oklahoma 74119
            Attn:  General Counsel



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            IN WITNESS WHEREOF, this Certificate of Merger has been executed on 
behalf of the surviving corporation by James R. Seward, its President and Chief 
Executive Officer, as of August 7, 1998.

                                            SLH CORPORATION
                                            a Kansas corporation




                                    By: /s/ James R. Seward
                                       -----------------------------------------
                                    Name:  James R. Seward
                                    Title: President and Chief Executive Officer



Attest:



/s/ Steven K. Fitzwater
- ---------------------------------
Steven K. Fitzwater, Secretary



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