SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549



                            ______________________

                                  FORM 8-K



                               CURRENT REPORT



                       Pursuant to Section 13 or 15(d) of
                      the Securities Exchange Act of 1934



                               Date of Report
                       (Date of earliest event reported)
                             September 27, 2000



                           UNION CARBIDE CORPORATION
           (Exact name of registrant as specified in its charter)



    New York                     1-1463                       13-1421730
(State or other         (Commission File Number)             (IRS Employer
jurisdiction of                                           Identification No.)
incorporation)





              39 Old Ridgebury Rd, Danbury, CT           06817-0001
          (Address of principal executive offices)       (Zip code)



                        Registrant's telephone number,
                      including area code 203-794-2000


                                Not applicable
        (Former name or former address, if changed since last report)






Item 5.  OTHER EVENTS


         With reference to the Agreement and Plan of Merger, dated as of
         August 3, 1999, among Union Carbide Corporation, a New York
         corporation ("Union Carbide"), The Dow Chemical Company, a Delaware
         corporation ("Dow Chemical"), and Transition Sub Inc., a Delaware
         corporation, Dow Chemical and Union Carbide have entered into a
         letter agreement filed herewith as Exhibit 99, which letter agreement
         was sent by Union Carbide to Dow Chemical on September 27, 2000 and
         executed by Dow Chemical on September 27, 2000.



Item 7.  FINANCIAL STATEMENTS AND EXHIBITS

         (C)  Exhibits.

              99.  Letter Agreement, dated September 27, 2000, with reference
                   to the Agreement and Plan of Merger, dated as of August 3,
                   1999, among Union Carbide Corporation, a New York
                   corporation, The Dow Chemical Company, a Delaware
                   corporation, and Transition Sub Inc., a Delaware
                   corporation.




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Pursuant to the requirements of the Securities Exchange Act of 1934, the
Registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.


Date:  September 27, 2000



                                        UNION CARBIDE CORPORATION

                                        /s/ J. Macdonald
                                        J. Macdonald
                                        Assistant Secretary


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                                 EXHIBIT INDEX

Exhibits

99.  Letter Agreement, dated September 27, 2000, with reference to the
     Agreement and Plan of Merger, dated as of August 3, 1999, among Union
     Carbide Corporation, a New York corporation, The Dow Chemical Company,
     a Delaware corporation, and Transition Sub Inc., a Delaware corporation.



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