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                                                                   Exhibit 4.12


                       AMENDMENT NO.1 TO WARRANT AGREEMENT



         This Amendment No.1 to Warrant Agreement is made as of this 31st day of
July, 1997, by and between The Edgehill Corporation (the "Holder"), Cryenco
Sciences, Inc., a Delaware corporation (f/k/a Cryenco Holdings, Inc.) 
("Cryenco") and Chart Industries, Inc., a Delaware corporation ("Chart").

         WHEREAS, the Holder and Cryenco are parties to a warrant agreement or
agreements (the "Warrant Agreement") dated as of December 20, 1994, pursuant to
which Cryenco granted the Holder a warrant or warrants (the "Cryenco Warrant")
to purchase an aggregate of 25,000 shares of Cryenco Class A common stock, par
value $.01 per share (the "Cryenco Common Stock");

         WHEREAS, Cryenco and Chart entered into a Plan and Agreement of Merger
dated as of April 30, 1997 (the "Merger Agreement") providing for the merger of
an affiliate of Chart into Cryenco (the "Merger") and the conversion of all
issued and outstanding Cryenco Common Stock (other than dissenters' shares) into
cash in the amount of $2.75 per share;

         WHEREAS, in Section 5.4(b)(iii) of the Merger Agreement, Chart has
agreed to offer to grant a substitute warrant (the "Chart Warrant") to purchase
shares of Chart's common stock, par value $.01 per share (the "Chart Common
Stock"), in exchange for the Cryenco Warrant; and

         WHEREAS, the Holder, Cryenco and Chart now desire that, in satisfaction
of Chart's obligations under Section 5.4(b)(iii) of the Merger Agreement, the
Cryenco Warrant be amended to provide the Holder with the right to purchase
Chart Common Stock in substitution for the right to purchase Cryenco Common
Stock;

         NOW, THEREFORE, in consideration of the foregoing, and the respective
agreements and undertakings set forth herein, the parties hereby agree as
follows:

         1.  DEFINITIONS. Capitalized terms not otherwise defined herein shall
have the meaning ascribed to them in the Merger Agreement.

         2.  AMENDMENT. As of the effective time of the Merger (the "Effective
Time"), the Warrant Agreement and the form of Cryenco Warrant referenced
therein are hereby amended as follows:

            (a)   CHART COMMON STOCK SUBSTITUTED FOR CRYENCO COMMON STOCK. All
                  references to the right of the Holder to purchase shares of
                  Cryenco Common Stock shall be deleted and the right to
                  purchase shares of Chart Common Stock shall be substituted
                  therefor.


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            (b)   ADJUSTMENT TO NUMBER OF SHARES UNDERLYING WARRANT. The
                  number of shares of Chart Common Stock issuable upon
                  exercise of the warrant shall be the product of (i) the
                  number of shares of Cryenco Common Stock that were issuable
                  upon exercise of the Cryenco Warrant times (ii) a fraction
                  (the "Exchange Ratio") the numerator of which shall be $2.75
                  and the denominator of which shall be the average of the
                  closing sales price of Chart Common Stock on the New York
                  Stock Exchange as reported by the Wall Street Journal for
                  the ten trading days preceding the Effective Time; provided,
                  however, that in no event shall the Exchange Ratio be less
                  than .165 nor more than .206.

            (c)   ADJUSTMENT TO PURCHASE OR EXERCISE PRICE. The purchase or
                  exercise price per share of Chart Common Stock subject to
                  the Chart Warrant shall be equal to (i) the purchase or
                  exercise price per share of Cryenco Common Stock divided by
                  (ii) the Exchange Ratio.

            (d)   NOTICES. Any notices, requests, forms, certificates or other
                  documents or communications deliverable to Cryenco under the
                  Warrant Agreement shall be required to be delivered instead
                  to Chart at 35555 Curtis Boulevard, Eastlake, OH 44095, to
                  the attention of the Chief Financial Officer, with a copy to
                  Calfee, Halter & Griswold LLP, 1400 McDonald Investment
                  Center, 800 Superior Avenue, Cleveland, OH 44114, Attention:
                  Thomas F. McKee.

            (e)   SUBMISSION TO JURISDICTION. Any provision in the Warrant
                  Agreement requiring that any action, claim or proceeding
                  arising out of, or relating in any way to, the Warrant
                  Agreement be brought exclusively in a jurisdiction located
                  in the State of Colorado shall be deleted in its entirety.

            (f)   SUBSTITUTION OF WARRANTS. Chart and the Holder agree that
                  any and all Warrants and/or Warrant Certificates issued
                  pursuant to the Warrant Agreement shall be amended in a
                  manner consistent with the provisions of this Amendment No.
                  1 and that, upon the Holder's presentation to Chart of such
                  Warrants or Warrant Certificates, Chart shall deliver to the
                  Holder, in exchange and substitution therefor, new Warrant
                  or Warrant Certificates.

      3.  FULL COMPLIANCE; ASSUMPTION OF CRYENCO'S OBLIGATIONS; REFERENCES TO
CRYENCO. The Holder acknowledges and agrees that, as of the Effective Time,
Cryenco is in full compliance with all of its obligations under the Warrant
Agreement, the Cryenco Warrant and any related agreements pertaining to
registration rights of the Holder with respect to the shares of Cryenco Common
Stock issuable upon exercise of the Warrants. As of the Effective Time, Chart
assumes all of the obligations of Cryenco under the Warrant Agreement as
amended hereby, and all references to Cryenco in the Warrant Agreement shall
be deemed to be 
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references to Chart. To the extent that Holder is party to a separate
registration rights agreement relating to Cryenco Common Stock, promptly after
the Effective Time, Chart and the Holder shall enter into such supplemental
agreement as may be necessary to provide the Holder with equivalent
registration rights relating to Chart Common Stock issuable upon exercise of
the Chart Warrant.


      4.  RECEIPT OF CHART DISCLOSURES. The Holder acknowledges that it has
received copies of Chart's 1996 Form 10-K Report and Chart's Form 10-Q Report
for the three-month period ended March 31, 1997.

      5.  NO RIGHT TO PURCHASE CRYENCO COMMON STOCK. At and after the Effective
Time, the Holder shall be deemed to have surrendered any and all rights under
the Warrant Agreement and Warrant to purchase Cryenco Common Stock.

      6.  CONSENT TO AMENDMENT. By the execution and delivery of this Amendment
No. 1, the Holder shall be deemed to have consented to the terms hereof in
accordance with the terms of the Warrant Agreement.

      7.  NO OTHER AMENDMENTS. Except as specifically provided herein or as
otherwise necessary or appropriate to effectuate the intent of this Amendment
No.1, the provisions of the Cryenco Warrant shall remain in full force and
effect without any alteration or modification thereto. Without limiting the
generality of the foregoing, the date of grant and the date of termination of
the Cryenco Warrant shall continue to be such dates as were in effect
immediately prior to the Effective Time.

      8.  SUCCESSORS AND ASSIGNS. This Agreement and all of the provisions
hereof shall be binding on and inure to the benefit of the parties hereto and
their respective successors and permitted assigns.

      9.  GOVERNING LAW. This Amendment No.1 shall be, and the Warrant
Agreement shall be amended to provide that it shall be, governed by and
construed in accordance with, the laws of the State of Delaware, without
giving effect to principles of conflicts of law.

      10. SEVERABILITY. If any one or more of the provisions contained herein,
or the application thereof in any circumstances, is held to be invalid,
illegal or unenforceable, the validity, legality and enforceability of any
such provision in every other respect and of the remaining provisions
contained herein shall not be affected or impaired thereby.

      11.  COUNTERPARTS. This Amendment No. 1 may be executed in one or more
counterparts, each of which when so executed shall be deemed to be an original
and all of which taken together shall constitute one and the same instrument.





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      IN WITNESS WHEREOF, the parties have executed this Amendment No.1 as of
the date first written above.

                                              CHART INDUSTRIES, INC.


Attest: /s/ Suzanne Lines                       /s/ Don A. Baines
      -----------------------------           ---------------------------------
                                              By:    Don A. Baines
                                              Title: CFO & Treasurer


                                              THE EDGEHILL CORPORATION



Attest:                                          /s/ Burton J. Ahrens
      -----------------------------           ---------------------------------
                                              By:    Burton J. Ahrens
                                              Title: President


                                              CRYENCO SCIENCES, INC.


Attest: /s/ Steven  M. Lutt                    /s/ James A. Raabe
      -----------------------------           ---------------------------------
                                              By:    James A. Raabe
                                              Title: VP & CFO







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