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                                                                      EXHIBIT 12

                 CABOT CORPORATION AND CONSOLIDATED SUBSIDIARIES
      STATEMENT REGARDING COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES

                      (Dollars in millions, except ratios)




                                                     Three
                                                    Months
                                                     ended
                                               December 31         Years ended September 30
                                               -----------  --------------------------------------
                                                      1998    1998    1997    1996    1995    1994
                                                      ----    ----    ----    ----    ----    ----

Earnings:
                                                                             
   Pre-tax income from continuing operations...      $48.0  $168.0  $117.0  $279.8  $256.0  $118.3
   Distributed income of affiliated companies..        1.1     7.5    10.4    11.2    11.7     5.6
   Add fixed charges:
     Interest on indebtedness..................       10.9    42.0    43.2    41.7    35.6    41.7
     Portion of rents representative of
       the interest factor.....................        1.3     5.1     4.9     4.8     5.5     5.9
                                                     -----  ------  ------  ------  ------  ------
  Income as adjusted...........................      $61.3  $222.6  $175.5  $337.5  $308.8  $171.5

Fixed charges:
  Interest on indebtedness.....................      $10.9   $42.0   $43.2   $41.7   $35.6   $41.7
  Portion of rents representative of
     the interest factor.......................        1.3     5.1     4.9     4.8     5.5     5.9
                                                     -----  ------  ------  ------  ------  ------

  Total fixed charges..........................      $12.2   $47.1   $48.1   $46.5   $41.1   $47.6

  Ratio of earnings to fixed charges...........        5.0     4.7     3.6     7.3     7.5     3.6
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