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                                                                   EXHIBIT 10.19


                               CheMatch.com, Inc.
                        2900 North Loop West, Suite 1120
                                Houston, TX 77092


February 2, 2000

Mr. Peter Singleton
William Heinemann Inc.
275 Washington Street
Newton, Mass.  02458

Via E-mail:  craig@reilaw.com

Dear Mr. Singleton,

         This letter will evidence our mutual understanding and agreement with
respect to the strategic alliance (the "Strategic Alliance") between
CheMatch.com, Inc., a Delaware corporation (the "Company") and William Heinemann
Inc. ("Purchaser") a Delaware corporation.

1.       Purchase of Company Common Stock by Purchaser.
         ---------------------------------------------

          (a)  Purchaser hereby agrees to purchase 153,218 shares of the
               Company's common stock, par value $.01 per share (the "Common
               Stock"), pursuant to a Subscription Agreement (in the form
               attached hereto as Exhibit A) for $1,500,004.22 in cash.

2.       Other Obligations and Agreements.
         --------------------------------

          (a)  Use of Names. Neither party to this agreement may reference the
               other party to this agreement in presentations, advertising,
               promotions or other published information without the other
               party's prior consent (which consent shall not be unreasonably
               withheld); provided, however, that either party may make such
               disclosure if in the reasonable opinion of such party's counsel
               such disclosure is required by law under the circumstances.

          (b)  Advertising and Information Agreement. The Company will purchase
               information content, advertising and other promotional material
               and services from Purchaser, or Purchaser's designee, in amounts
               totaling at least $500,000.00 during the two-year period
               beginning January 1, 2000. Each item of content, advertising or
               other service will be priced from time to time as mutually agreed
               by the parties.

3.       Miscellaneous.
         -------------

          (a)  The Strategic Alliance, this letter agreement and all
               documentation contemplated by this letter shall be governed by
               the laws of the State of Texas, without regard to any conflict of
               laws principles.

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          (b)  Each of Purchaser and the Company will bear its own costs and
               expenses of the preparation of the documentation and performance
               of the obligations set forth in this letter.

         If this letter correctly sets forth our understanding, please indicate
your acceptance by executing this letter in the space provided below.


                                            Very truly yours,



                                            CheMatch.com, Inc.

                                            By:  /s/ CARL D. MCCUTCHEON
                                               ----------------------------



ACCEPTED AND AGREED TO
THIS 11th DAY OF FEBRUARY, 2000:

WILLIAM HEINEMANN INC.

By: /s/ HENRY Z. HORBACZWESKI
   ----------------------------
Name: Henry Z. Horbaczweski
Title: Senior Vice President and
        General Counsel


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