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                UNITED STATES SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549
                                        
                                  FORM 10-K/A
                          AMENDMENT NO.1 TO FORM 10-K

           [X] ANNUAL REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

                 For the Fiscal Year ended September 30, 1996

                                      OR

         [ ] TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE
                        SECURITIES EXCHANGE ACT OF 1934

     For the Transiton Period from .................. to ................

                         COMMISSION FILE NUMBER 1-5667

                               CABOT CORPORATION
            (Exact name of Registrant as specified in its charter)

          DELAWARE                                      04-2271897
     (State or other jurisdiction                     (IRS Employer
     of incorporation or organization)             Identification No.)

          75 STATE STREET
        BOSTON, MASSACHUSETTS                             02109
     (Address of Principal Executive Offices)           (Zip Code)

                                (617) 345-0100
             (Registrant's telephone number, including area code)

Securities registered pursuant to section 12(b) of the act:
     Common Stock, $1.00 par value per share:
     70,446,881 shares outstanding            Boston Stock Exchange
     at November 29, 1996                     New York Stock Exchange
                                              Pacific Stock Exchange
     Preferred Stock Purchase Rights

     Indicate by check mark whether the Registrant (1) has filed all reports
required to be filed by Section 13 or 15(d) of the Securities Exchange Act of
1934 during the preceding 12 months (or for such shorter period that the
Registrant was required to file such reports), and (2) has been subject to such
filing requirements for the past 90 days.   Yes [X]  No [ ]

     Indicate by check mark if disclosure of delinquent filers pursuant to Item
405 of Regulation S-K is not contained herein, and will not be contained, to the
best of the Registrant's knowledge, in the definitive proxy or information
statements incorporated by reference in Part III of this Form 10-K or any
amendment to this Form 10-K. [ ]

     The aggregate market value of the Registrant's common stock held
beneficially or of record by shareholders who are not directors or executive
officers of the Registrant at November 29, 1996, was approximately
$1,634,283,000.

                      DOCUMENTS INCORPORATED BY REFERENCE

     Portions of the Registrant's Annual Report to Stockholders for fiscal year
1996 are incorporated by reference in Parts II and IV, and portions of the
Registrant's definitive Proxy Statement for  its 1997 Annual Meeting of
Stockholders are incorporated by reference in Part III.

 
     The undersigned registrant hereby amends its Annual Report on Form 10-K for
the fiscal year ended September 30, 1996 to add the "Consent of Independent
Accountants" as set forth below:


                       Consent of Independent Accountants

     We consent to the incorporation by reference in the registration statements
of Cabot Corporation on Form S-3 (File No. 33-48686), and on Forms S-8 (File No.
33-28699, No. 33-52940, No. 33-53659, No. 333-03683, No. 333-06629, No.333-19099
and No. 333-19103) of our report dated October 25, 1996, on our audits of the
consolidated financial statements of Cabot Corporation as of September 30, 1996
and 1995, and for each of the three years in the period ended September 30,
1996, which report is included in the 1996 Annual Report to Stockholders of
Cabot Corporation, filed as Exhibit 13 to the Annual Report on Form 10-K for the
fiscal year ended September 30, 1996.


                                         Coopers & Lybrand L.L.P.

Boston, Massachusetts
January 31, 1997


                                  SIGNATURES

     Pursuant to the requirements of Section 13 or 15(d) of the Securities
Exchange Act of 1934, the registrant has duly caused this amendment to be signed
on its behalf by the undersigned, thereunto duly authorized.

                                         CABOT CORPORATION (Registrant)



                                         By: /s/ William F. Robinson, Jr.
                                         -----------------------------------
                                                 William F. Robinson, Jr.
                                                   Assistant Secretary

Dated:  January 31, 1997