SCHEDULE 14A
                                 (RULE 14A-101)

                    INFORMATION REQUIRED IN PROXY STATEMENT

                            SCHEDULE 14A INFORMATION
                PROXY STATEMENT PURSUANT TO SECTION 14(A) OF THE 
                SECURITIES EXCHANGE ACT OF 1934 (AMENDMENT NO. )

Filed by the Registrant [X]

Filed by a Party other than the Registrant [ ]

[ ]  Preliminary Proxy Statement          [ ]  Confidential, for Use of the
                                               Commission Only (as permitted 
                                               by Rule 14a-6(e)(2))
[ ]  Definitive Proxy Statement

[X]  Definitive Additional Materials

[ ]  Soliciting Material Pursuant to Rule 14a-11(c) or Rule 14a-12

                          UNION CARBIDE CORPORATION
               (Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement, if other than the Registrant)

Payment of Filing Fee (Check the appropriate box):

[X]   No fee required.

[ ]   Fee computed on table below per Exchange Act Rule 14a-6(i)(1) and 0-11.

          (1)  Title of each class of securities to which transaction applies:

          (2)  Aggregate number of securities to which transaction applies:

          (3)  Per unit price or other underlying value of transaction
               computed pursuant to Exchange Act Rule 0-11 (set forth
               the amount on which the filing fee is calculated and
               state how it was determined):

          (4)  Proposed maximum aggregate value of transaction:

          (5)  Total fee paid:

[ ]     Fee paid previously with preliminary materials:

[ ]     Check box if any part of the fee is offset as provided by Exchange Act
        Rule 0-11 (a) (2) and identify the filing for which the offsetting fee
        was paid previously.  Identify the previous filing by registration
        statement number, or the Form or Schedule and the date of its filing.

          (1)  Amount Previously Paid:

          (2)  Form, Schedule or Registration Statement No.:

          (3)  Filing Party:

          (4)  Date Filed: 


                                                 April 22, 1999 



A message from Bruce Fitzgerald, Vice President, General Counsel and 
Secretary, to Carbiders:

      As an owner of Union Carbide shares, you have the right to vote on 
three issues to be addressed at our company's annual meeting of 
stockholders that will be held on April 28, 1999.  IF YOU HAVE NOT YET 
VOTED, WE URGE YOU TO VOTE NOW. 

      YOUR VOTE IS PARTICULARLY IMPORTANT BECAUSE YOUR BOARD OF 
DIRECTORS UNANIMOUSLY RECOMMENDS THAT SHAREHOLDERS VOTE AGAINST PROPOSAL 
3 ON THIS YEAR'S AGENDA.  If you have already voted in favor of Proposal 
3, we ask you to reconsider for the reasons stated in the proxy 
statement. Because of the late date, we ask that you vote via telephone 
as instructed on the proxy card previously sent to you.*  If you have 
voted AGAINST Proposal 3, we thank you for your support.

      YOUR VOTE COUNTS. 

      PLEASE VOTE.  PLEASE VOTE AGAINST PROPOSAL 3.



      *  If  you no longer have your proxy card, please send an e-mail 
message, no later than close of business on Friday, to Landi DL (Donna) 
or to Porricelli DC (Don) to request a duplicate proxy card.  Be sure to 
include your fax number.