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                                                                 EXHIBIT 5.1


                   [WEIL, GOTSHAL & MANGES LLP LETTERHEAD]


                                 August 4, 1998



Thermadyne Mfg. LLC
Thermadyne Capital Corp.
101 South Hanley Road, Suite 300
St. Louis, Missouri  63105

Ladies and Gentlemen:

              We have acted as counsel to Thermadyne Mfg. LLC, a Delaware
limited liability company (the "Company"), and Thermadyne Capital Corp., a
Delaware corporation (together with the Company, the "Issuers"), in connection
with the preparation and filing by the Issuers and by C&G Systems, Inc., an
Illinois corporation ("C&G"), Coyne Natural Gas Systems Inc., a Missouri
corporation ("CNGS"), Modern Engineering Company, Inc., a Missouri corporation
("MECO"), Wichita Warehouse Corporation, a Kansas corporation ("WWC"), C&G
Systems Holding, a Delaware corporation, Marison Cylinder Corporation, a
Delaware corporation, MECO Holding Company, a Delaware corporation, Stoody
Company, a Delaware corporation, Tag Realty, Inc., a Texas corporation,
Thermadyne Cylinder Company, a California corporation ("TCC"), Thermadyne
Industries, Inc., a Delaware corporation, Thermadyne International Corp., a
Delaware corporation, Thermal Arc, Inc., a Delaware corporation, Thermal
Dynamics Corp., a Delaware corporation, Tweco Products, Inc., a Delaware
corporation, Victor Coyne International, Inc., a Delaware corporation, Victor
Equipment Company, a Delaware corporation, and Woodland Cryogenics Company, a
Delaware corporation (collectively, the "Subsidiary Guarantors"), of a
Registration Statement on Form S-1 (Registration No. 333-57455) (the
"Registration Statement"), filed with the Securities and Exchange Commission on
June 23, 1998 under the Securities Act of 1933, as amended, relating to
$207,000,000 aggregate principal amount of 9 7/8% Senior Subordinated Notes due
2008 (the "New Notes") of the Issuers and the related guarantees thereof by the
Subsidiary Guarantors (the "Guarantees").  The Issuers and the Subsidiary
Guarantors propose to offer (the "Exchange Offer"), upon the terms set forth in
the Prospectus contained in the Registration Statement, to exchange $1,000
principal amount of New Notes and the related Guarantees for each $1,000
principal amount of issued and outstanding 9 7/8% Senior Subordinated Notes due
2008 of the Issuers (the "Old Notes") and the related
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Thermadyne Mfg. LLC
Thermadyne Capital Corp.
August 4, 1998
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guarantees thereof by the Subsidiary Guarantors.  The New Notes and the related
Guarantees will be issued under the Indenture, dated May 22, 1998, by and among
the Issuers, the Subsidiary Guarantors and State Street Bank and Trust Company
(the "Trustee") (as amended or supplemented to the date hereof, the
"Indenture").

              In so acting, we have examined originals or copies, certified or
otherwise identified to our satisfaction, of the Indenture, the form of New
Notes set forth in the Indenture and such corporate records, agreements,
documents and other instruments, and such certificates or comparable documents
of public officials and of officers and representatives of the Issuers and the
Subsidiary Guarantors (such companies herein referred to collectively as the
"Thermadyne Companies"), and have made such inquiries of such officers and
representatives as we have deemed relevant and necessary as a basis for the
opinions hereinafter set forth.

              In such examination, we have assumed the genuineness of all
signatures, the legal capacity of natural persons, the authenticity of all
documents submitted to us as originals, the conformity to original documents of
all documents submitted to us as certified, conformed or photostatic copies and
the authenticity of the originals of such latter documents.  As to all
questions of fact material to this opinion that have not been independently
established, we have relied upon certificates or comparable documents of
officers and representatives of the Thermadyne Companies.  We have also assumed
(i) the due incorporation or formation and valid existence of the Thermadyne
Companies, (ii) that C&G, CNGS, MECO, WWC and TCC have the requisite corporate
power and authority to enter into and perform the Indenture, (iii) the due
authorization, execution and delivery of the Indenture by C&G, CNGS, MECO, WWC
and TCC and (iv) that the issuance of the Guarantees upon consummation of the
Exchange Offer has been duly authorized by C&G, CNGS, MECO, WWC and TCC.

              Based on the foregoing, and subject to the qualifications stated
herein, we are of the opinion that:

              1.     Assuming that the Indenture has been duly authorized,
executed and delivered by the Trustee, when (i) the New Notes issuable upon
consummation of the Exchange Offer have been duly executed by the Issuers and
authenticated by the Trustee in accordance with the terms of the Indenture and
(ii) the New Notes issuable upon consummation of the Exchange Offer have been
duly delivered against receipt of Old Notes surrendered in exchange therefor,
the New Notes issuable upon consummation of the Exchange Offer will constitute
the legal, valid and binding obligations of the Issuers, enforceable against
them in accordance with their terms, subject to applicable bankruptcy,
insolvency, fraudulent conveyance, reorganization, moratorium and similar laws
affecting creditors' rights and remedies generally, and subject, as to
enforceability, to general principles of equity, including principles of
commercial reasonableness,





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Thermadyne Mfg. LLC
Thermadyne Capital Corp.
August 4, 1998
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good faith and fair dealing (regardless of whether enforcement is sought in a
proceeding at law or in equity).

              2.     Assuming that the Indenture has been duly authorized,
executed and delivered by the Trustee, when (i) the New Notes issuable upon
consummation of the Exchange Offer have been duly executed by the Issuers and
authenticated by the Trustee in accordance with the terms of the Indenture and
(ii) the New Notes issuable upon consummation of the Exchange Offer have been
duly delivered against receipt of Old Notes surrendered in exchange therefor,
the Guarantees issuable upon consummation of the Exchange Offer will constitute
the legal, valid and binding obligations of the Subsidiary Guarantors,
enforceable against them in accordance with their terms, subject to applicable
bankruptcy, insolvency, fraudulent conveyance, reorganization, moratorium and
similar laws affecting creditors' rights and remedies generally, and subject,
as to enforceability, to general principles of equity, including principles of
commercial reasonableness, good faith and fair dealing (regardless of whether
enforcement is sought in a proceeding at law or in equity).

              The opinions expressed herein are limited to the laws of the
State of New York, the corporate laws of the State of Delaware and the federal
laws of the United States, and we express no opinion as to the effect on the
matters covered by this letter of the laws of any other jurisdiction.

              The opinions expressed herein are rendered solely for your
benefit in connection with the transactions described herein.  Those opinions
may not be used or relied upon by any other person, nor may this letter or any
copies thereof be furnished to a third party, filed with a governmental agency,
quoted, cited or otherwise referred to without our prior written consent.

              We hereby consent to the filing of this opinion as an exhibit to
the Registration Statement and the reference to this firm under the caption
"Legal Matters" in the Prospectus forming a part of the Registration Statement.


                                           Very truly yours,

                                           /s/ WEIL, GOTSHAL & MANGES LLP