EXHIBIT 10.58


                           ALLIS-CHALMERS CORPORATION
                            5075 Westheimer Suite 890
                              Houston, Texas 77056


                               September 29, 2004


VIA FAX AND E-MAIL SEMERSON@EMERSONIG.COM
- -----------------------------------------

Steve Emerson
Emerson Investments


         RE: PRIVATE PLACEMENT OF COMMON STOCK BY ALLIS-CHALMERS CORPORATION
             ---------------------------------------------------------------

Dear Mr. Emerson:

         The purpose of this letter is to confirm that, in connection with your
investment in the Common Stock of Allis-Chalmers Corporation pursuant to the
Stock Purchase Agreement dated August 10, 2004 (the "Stock Purchase Agreement"):

   (1)   you will not be required to suspend sales of shares pursuant to the
         Registration Statement (as defined in the Stock Purchase Agreement) as
         a result of any secondary offering of shares by the Allis-Chalmers
         Corporation;

   (2)   Section 6.4 of the Stock Purchase Agreement shall not be deemed to
         reduce Allis-Chalmers Corporation's obligations under the last sentence
         of Section 6.2 of the Stock Purchase Agreement (except with respect to
         a person eligible to sell all Shares in a single transaction pursuant
         to Rule 144); and

   (3)   With respect to Section 1 of the Amendment to Stock Purchase Agreement
         dated August 10, 2004: during the referenced six month period the
         Company will not issue any rights to acquire, or enter into any
         agreement involving the issuance of, its Common Stock, unless (a) the
         transaction is one contemplated by said Section 1, i.e., the issuance
         of Common Stock or convertible securities for cash (and not the
         issuance of other types of securities or a bundle of two or more types
         of securities), or (b) the Company and you mutually agree upon the
         number of additional shares of Common Stock to be issued to



Steve Emerson
Emerson Investments
September 29, 2004
Page 2


         you in order to achieve the objectives of said Section 1, i.e., that
         you obtain the same value for your investment as any subsequent
         investor during the six month period.


                                   Sincerely,

                                   /s/ Todd A. Seward

                                   Todd A. Seward,
                                   Chief Accounting Officer