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                                                                     Exhibit 5.1


                        SQUIRE, SANDERS & DEMPSEY L.L.P.
                                 4900 KEY TOWER
                                127 PUBLIC SQUARE
                           CLEVELAND, OHIO 44114-1304



   
                                  May 14, 1999
    



Cooper Industries, Inc.
600 Travis, Suite 5800
Houston, Texas 77002

Ladies and Gentlemen:

         Reference is made to the Registration Statement on Form S-3 (the
"Registration Statement") to be filed by Cooper Industries, Inc. (the "Company")
with respect to $500,000,000 in aggregate principal amount of debt securities
(the "Debt Securities") to be issuable under an indenture between the Company
and The Chase Manhattan Bank, as Trustee (the "Indenture"). We have examined the
forms of the Indenture and the Debt Securities being filed as exhibits to the
Registration Statement and such other documents and matters of law as we have
deemed necessary for purposes of this opinion.

         Based upon the foregoing, we are of the opinion that the Debt
Securities, when executed by the Company and authenticated by the Trustee in
accordance with the provisions of the Indenture, and when issued and sold by the
Company as contemplated in the Registration Statement, will constitute valid and
binding obligations of the Company and will be entitled to the benefits of the
Indenture, subject to applicable bankruptcy, insolvency, moratorium,
reorganization, fraudulent transfer or similar laws affecting the enforcement of
creditors' rights generally and subject to general principles of equity (whether
considered in a proceeding at law or in equity).

         We hereby consent to the filing of this opinion as an exhibit to the
Registration Statement and to the reference to our firm under the caption "Legal
Matters" in the prospectus contained therein.



                                           Respectfully submitted,



                                           /s/ Squire, Sanders & Dempsey L.L.P.