FORM 10-Q

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549

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

For the quarterly period ended

DECEMBER 31, 1996

or

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

For the transition period from ________ to ________

COMMISSION FILE NUMBER 1-5667

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

                DELAWARE                                  04-2271897
        (State of Incorporation)            (I.R.S. Employer Identification No.)

             75 STATE STREET                             02109-1806
          BOSTON, MASSACHUSETTS                           (Zip Code)
(Address of principal executive offices)

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

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, and (2) has been subject to such filing requirements for the past 90 days.

YES X NO

Indicate the number of shares outstanding of each of the issuer's classes of Common Stock, as of the latest practicable date.

AS OF DECEMBER 31, 1996, THE COMPANY HAD 70,148,885 SHARES OF COMMON

STOCK, PAR VALUE $1 PER SHARE, OUTSTANDING.

-1-

CABOT CORPORATION

INDEX

Part I.  Financial Information                                             Page No.
                                                                           --------
         Item 1.    Financial Statements

                    Consolidated Statements of Income
                         Three Months Ended December 31, 1996 and 1995         3

                    Consolidated Balance Sheets
                         December 31, 1996 and September 30, 1996              4

                    Consolidated Statements of Cash Flows
                         Three Months Ended December 31, 1996 and 1995         6

                    Notes to Consolidated Financial Statements                 7

         Item 2.    Management's Discussion and Analysis of Financial
                         Condition and Results of Operations                   9


Part II.  Other Information

         Item 6.    Exhibits and Reports on Form 8-K                          12

-2-

Part I. Financial Information

Item 1. Financial Statements

CABOT CORPORATION
CONSOLIDATED STATEMENTS OF INCOME
Three Months Ended December 31, 1996 and 1995

(Dollars in thousands, except per share amounts)

UNAUDITED

                                                           1996             1995
                                                        ---------        ---------
Revenues:
   Net sales and other operating revenues               $ 398,825        $ 443,031
   Interest and dividend income                             1,679            2,461
                                                        ---------        ---------
     Total revenues                                       400,504          445,492
                                                        ---------        ---------

Costs and expenses:
   Cost of sales                                          279,683          305,133
   Selling and administrative expenses                     53,660           46,631
   Research and technical service                          20,926           14,277
   Interest expense                                         9,670            9,421
   Other charges, net                                       1,821            5,273
                                                        ---------        ---------
     Total costs and expenses                             365,760          380,735
                                                        ---------        ---------

Income before income taxes                                 34,744           64,757
Provision for income taxes                                (12,507)         (23,960)
Equity in net income of affiliated companies                3,974            3,723
Minority interest                                          (1,098)          (1,169)
                                                        ---------        ---------

Net income                                                 25,113           43,351

Dividends on preferred stock, net of tax
   benefit of $524 and $475                                  (820)            (883)
                                                        ---------        ---------

Income applicable to primary common shares              $  24,293        $  42,468
                                                        =========        =========


Weighted average common shares outstanding (000):
   Primary                                                 72,019           75,114
   Fully diluted (Note A)                                  78,088           81,318

Income per common share:
   Primary                                              $    0.34        $    0.57
                                                        =========        =========
   Fully diluted (Note A)                               $    0.32        $    0.53
                                                        =========        =========

Dividends per common share                              $    0.10        $    0.09
                                                        =========        =========

The accompanying notes are an integral part of these financial statements.

-3-

CABOT CORPORATION
CONSOLIDATED BALANCE SHEETS
December 31, 1996 and September 30, 1996

(Dollars in thousands)

ASSETS

                                                December 31       September 30
                                                    1996              1996
                                                (Unaudited)
                                                -----------        -----------
Current assets:
   Cash and cash equivalents                    $    42,328        $    58,148
   Accounts and notes receivable
     (net of reserve for doubtful
      accounts of $4,813 and $5,267)                292,041            363,763

   Inventories:
     Raw materials                                   79,591             71,061
     Work in process                                 68,103             72,914
     Finished goods                                  83,097             72,163
     Other                                           43,889             44,292
                                                -----------        -----------
       Total inventories                            274,680            260,430

   Prepaid expenses                                  18,897             17,408
   Deferred income taxes                             10,424             10,034
                                                -----------        -----------

Total current assets                                638,370            709,783
                                                -----------        -----------

Investments:
   Equity                                            79,826             79,372
   Other                                            106,223             95,680
                                                -----------        -----------
     Total investments                              186,049            175,052
                                                -----------        -----------

Property, plant and equipment                     1,777,003          1,712,045
Accumulated depreciation and amortization          (836,036)          (809,053)
                                                -----------        -----------
   Net property, plant and equipment                940,967            902,992
                                                -----------        -----------

Other assets:
   Intangible assets, net of amortization            41,782             42,735
   Deferred income taxes                              2,494              2,402
   Other assets                                      26,497             24,617
                                                -----------        -----------
     Total other assets                              70,773             69,754
                                                -----------        -----------

Total assets                                    $ 1,836,159        $ 1,857,581
                                                ===========        ===========

The accompanying notes are an integral part of these financial statements.

-4-

CABOT CORPORATION
CONSOLIDATED BALANCE SHEETS
December 31, 1996 and September 30, 1996

(Dollars in thousands)

LIABILITIES & STOCKHOLDERS' EQUITY

                                                                   December 31         September 30
                                                                       1996                  1996
                                                                   (Unaudited)
                                                                    -----------        -----------
Current liabilities:
   Notes payable to banks                                           $   244,520        $   233,779
   Current portion of long-term debt                                    114,570             16,175
   Accounts payable and accrued liabilities                             232,211            250,749
   U.S. and foreign income taxes payable                                 20,486             26,083
   Deferred income taxes                                                    953                918
                                                                    -----------        -----------
     Total current liabilities                                          612,740            527,704
                                                                    -----------        -----------

Long-term debt                                                          219,796            321,497
Deferred income taxes                                                    91,748             88,320
Other liabilities                                                       151,024            147,991

Commitments and contingencies (Note B)

Minority interest                                                        26,697             27,138

Stockholders' Equity (Note C):

Preferred Stock:
   Authorized:  2,000,000 shares of $1 par value
   Series A Junior Participating Preferred Stock
     Issued and outstanding:  none
   Series B ESOP Convertible Preferred Stock 7.75% Cumulative
     Issued:  75,336 shares (aggregate redemption value
     of $70,671 and $71,193)                                             75,336             75,336

Less cost of shares of preferred treasury stock                          (7,089)            (6,565)

Common stock:
   Authorized:  200,000,000 shares of $1 par value
   Issued:  135,549,936 shares                                          135,550            135,550

Additional paid-in capital                                               23,993             23,618

Retained earnings                                                     1,193,791          1,176,708

Less cost of common treasury stock
   (including unearned amounts of $13,791 and $16,611)                 (685,292)          (650,981)

Deferred employee benefits                                              (63,855)           (64,283)

Unrealized gain on marketable securities                                 34,253             29,874

Foreign currency translation adjustments                                 27,467             25,674
                                                                    -----------        -----------

Total stockholders' equity                                              734,154            744,931
                                                                    -----------        -----------

Total liabilities and stockholders' equity                          $ 1,836,159        $ 1,857,581
                                                                    ===========        ===========

The accompanying notes are an integral part of these financial statements.

-5-

CABOT CORPORATION
CONSOLIDATED STATEMENTS OF CASH FLOWS
Three Months Ended December 31, 1996 and 1995

(Dollars in thousands)

UNAUDITED

                                                                   1996            1995
                                                                 --------        ---------
CASH FLOWS FROM OPERATING ACTIVITIES:

Net income                                                       $ 25,113        $  43,351
Adjustments to reconcile net income to cash
   provided by operating activities:
     Depreciation and amortization                                 27,041           23,542
     Deferred tax provision                                          (490)              62
     Equity in net income of affiliated companies,
       net of dividends received                                   (1,629)            (258)
     Other, net                                                     2,165            2,414

   Changes in assets and liabilities, net of consolidation
     of equity affiliates:
     (Increase) decrease in accounts receivable                   (11,637)             837
     Increase in inventory                                        (13,584)         (34,677)
     Decrease in accounts payable and accruals                    (19,342)         (17,283)
     Increase in prepayments and intangible assets                 (3,102)            (695)
     Decrease in income taxes payable                              (5,688)            (266)
     Other, net                                                     1,992          (29,295)
                                                                 --------        ---------

   Cash (used) provided by operating activities                       839          (12,268)

CASH FLOWS FROM INVESTING ACTIVITIES:

   Additions to property, plant and equipment                     (58,648)         (28,621)
   Proceeds on sale of business                                    35,000
   Investments and acquisitions                                    (3,962)
   Cash from consolidation of equity affiliates                                      9,306
   Other                                                              101            1,254
                                                                 --------        ---------

     Cash used by investing activities                            (27,509)         (18,061)

CASH FLOWS FROM FINANCING ACTIVITIES:

   Repayments of long-term debt                                    (3,684)         (10,247)
   Increase in short-term debt                                     59,754          103,345
   Purchases of treasury stock                                    (38,217)         (90,410)
   Sales and issuances of treasury stock                            1,407            2,025
   Cash dividends paid to stockholders                             (8,031)          (7,499)
   Redemption of preferred stock purchase rights                                    (1,840)
                                                                 --------        ---------

     Cash used by financing activities                             11,229           (4,626)

Effect of exchange rate changes on cash                              (379)             159
                                                                 --------        ---------

Decrease in cash and cash equivalents                             (15,820)         (34,796)

Cash and cash equivalents at beginning of period                   58,148           90,792
                                                                 --------        ---------

Cash and cash equivalents at end of period                       $ 42,328        $  55,996
                                                                 ========        =========

The accompanying notes are an integral part of these financial statements.

-6-

CABOT CORPORATION

NOTES TO CONSOLIDATED FINANCIAL STATEMENTS
December 31, 1996

A. SIGNIFICANT ACCOUNTING POLICIES

Principles of Consolidation

The consolidated financial statements include the accounts of Cabot Corporation and majority-owned and controlled domestic and foreign subsidiaries. Investments in majority-owned affiliates where control does not exist and investments in 20 percent to 50 percent owned affiliates are accounted for on the equity method.

The financial statements have been prepared in accordance with the requirements of Form 10-Q and consequently do not include all disclosures required by Form 10-K. Additional information may be obtained by referring to the Company's Form 10-K for the year ended September 30, 1996.

The financial information submitted herewith is unaudited and reflects all adjustments which are, in the opinion of management, necessary to provide a fair statement of the results for the interim periods ended December 31, 1996 and 1995. All such adjustments are of a normal recurring nature. The results for interim periods are not necessarily indicative of the results to be expected for the fiscal year.

Earnings Per Share

The computation of fully diluted earnings per share considers the conversion of the Company's Series B ESOP Convertible Preferred Stock held by the Company's Employee Stock Ownership Plan, and also includes the potentially dilutive effects of the Company's Equity Incentive Plan adopted in 1989 and the 1996 Equity Incentive Plan.

Reclassification

Certain amounts in fiscal 1996 have been reclassified to conform to the fiscal 1997 presentation.

B. COMMITMENTS AND CONTINGENCIES

The Company has various lawsuits, claims and contingent liabilities. In the opinion of the Company, although final disposition of all of its suits and claims may impact the Company's financial statements in a particular period, they should not, in the aggregate, have a material adverse effect on the Company's financial position. As of the end of the quarter, approximately $37 million was committed for various capital projects.

-7-

CABOT CORPORATION
NOTES TO CONSOLIDATED FINANCIAL STATEMENTS - (Continued)
December 31, 1996
UNAUDITED

C. STOCKHOLDERS' EQUITY The following table summarizes the changes in stockholders' equity for the three months ended December 31, 1996.

(Dollars in thousands)

                                                Preferred Stock         Preferred                   Common Stock
                                                ---------------       Treasury Stock                ------------
                                               Shares                 --------------           Shares
                                               Issued      Value     Shares      Cost          Issued         Value
                                               ------     -------     -----     -------      -----------     --------

Balance at September 30, 1996                  75,336     $75,336     5,744     $(6,565)     135,549,936     $135,550

Net income

Common stock dividends paid

Issuance of treasury stock under
   employee compensation plans

Purchase of treasury stock - common

Purchase of treasury stock - preferred                                  213        (524)

Sale of treasury stock to Cabot
Retirement Incentive Savings Plan

Preferred stock dividends paid to Employee
   Stock Ownership Plan, net of tax

Principal payment by Employee Stock
   Ownership Plan under guaranteed loan

Amortization of unearned compensation

Unrealized gain, net of deferred tax

Foreign currency translation adjustments
                                               ------     -------     -----     -------      -----------     --------
Balance at December 31, 1996                   75,336     $75,336     5,957     $(7,089)     135,549,936     $135,550
                                               ======     =======     =====     =======      ===========     ========

                                                                                       Common
                                               Additional                           Treasury Stock
                                                Paid-in       Retained              --------------            Unearned
                                                Capital       Earnings           Shares           Cost      Compensation
                                               --------      -----------      -----------      ---------    ------------
Balance at September 30, 1996                  $ 23,618      $ 1,176,708       63,960,725      $(634,370)     $(16,611)

Net income                                                        25,113

Common stock dividends paid                                       (7,210)

Issuance of treasury stock under
   employee compensation plans                     (216)                          (24,344)           174           470

Purchase of treasury stock - common                                             1,503,460        (37,693)

Purchase of treasury stock - preferred

Sale of treasury stock to Cabot
Retirement Incentive Savings Plan                   591                           (38,790)           388

Preferred stock dividends paid to Employee
   Stock Ownership Plan, net of tax                                 (820)

Principal payment by Employee Stock
   Ownership Plan under guaranteed loan

Amortization of unearned compensation                                                                            2,350

Unrealized gain, net of deferred tax

Foreign currency translation adjustments
                                               --------      -----------      -----------      ---------      --------
Balance at December 31, 1996                   $ 23,993      $ 1,193,791       65,401,051      $(671,501)     $(13,791)
                                               ========      ===========      ===========      =========      ========

                                                                Unrealized      Foreign
                                                 Deferred       Gain/(Loss)     Currency        Total
                                                 Employee       Marketable     Translation   Stockholders'
                                                 Benefits       Securities     Adjustments      Equity
                                                 --------       ----------     -----------     ---------
Balance at September 30, 1996                    $(64,283)       $29,874         $25,674       $ 744,931

Net income                                                                                        25,113

Common stock dividends paid                                                                       (7,210)

Issuance of treasury stock under
   employee compensation plans                                                                       428

Purchase of treasury stock - common                                                              (37,693)

Purchase of treasury stock - preferred                                                              (524)

Sale of treasury stock to Cabot
Retirement Incentive Savings Plan                                                                    979

Preferred stock dividends paid to Employee
   Stock Ownership Plan, net of tax                                                                 (820)

Principal payment by Employee Stock
   Ownership Plan under guaranteed loan               428                                            428

Amortization of unearned compensation                                                              2,350

Unrealized gain, net of deferred tax                                 4,379                         4,379

Foreign currency translation adjustments                                           1,793           1,793
                                                 --------          -------       -------       ---------
Balance at December 31, 1996                     $(63,855)         $34,253       $27,467       $ 734,154
                                                 ========          =======       =======       =========

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CABOT CORPORATION

Item 2. Management's Discussion and Analysis of
Financial Condition and Results of Operations

I. RESULTS OF OPERATIONS

Sales and operating profit by industry segment are shown in the accompanying table on page 11.

THREE MONTHS ENDED DECEMBER 31, 1996 VERSUS
THREE MONTHS ENDED DECEMBER 31, 1995

Net income for the first quarter of fiscal 1997 was $25.1 million ($0.32 per common share, fully diluted), compared with net income of $43.4 million ($0.53 per common share, fully diluted) in the same quarter a year ago. Net sales and other operating revenues decreased 10% to $398.8 million from $443.0 million. Total operating profit was $50.4 million for the quarter, compared to $80.1 million in the same quarter a year ago, reflecting lower margins in the Company's carbon black business. Results for the first quarter of fiscal 1996 included $65.7 million of revenues and $2.9 million of operating profit from the Company's former coal handling subsidiary, which was sold at the end of that fiscal year.

In the Specialty Chemicals and Materials Group, net sales were $340.2 million, compared with $344.0 million last year. The effects of greater specialty chemical volumes globally were more than offset by the effects of lower carbon black selling prices, primarily in the European and Pacific Asia markets. The Group reported operating profit of $45.9 million for the first quarter, compared with $71.8 million for the first quarter of fiscal 1996. More than half of the year-to-year decrease in operating profit occurred in the Company's European carbon black business. Price concessions made during 1996 and higher year-to-year feedstock costs, which the Company could not recover from its customers, resulted in tighter margins in that business. Higher year-to-year feedstock costs also affected North American carbon black margins during the first quarter, but were partially offset by higher selling prices.

The Company's Performance Materials Division (CPM), which primarily manufactures tantalum products, experienced 20% lower volumes in the first quarter compared to the same quarter last year. CPM's customers continued to draw down their tantalum inventories from excessive levels caused by a slowdown in the U.S. electronics industry market during 1996.

The Cab-O-Sil fumed silica business reported increased earnings for the first quarter, due primarily to an 18% increase in volumes from the first quarter of last year.

As expected, increased spending on research and development and marketing costs associated with new product, new business and market development initiatives accounted for $6.8 million of the year-to-year operating profit decrease. The Company is pursuing a number of new product and new business development opportunities as part of a growth strategy.

In the Energy Group, sales decreased to $58.6 million from $99.0 million in the first quarter of fiscal 1996. The first quarter of fiscal 1996 results included revenues of $65.7 million from the Company's former coal handling subsidiary, TUCO INC. The Company sold TUCO at the end of fiscal 1996. Excluding TUCO revenues from the Energy Group's 1996 results to form a comparative basis, the Group's revenues increased 76% in the first quarter of fiscal 1997.

-9-

CABOT CORPORATION

Management's Discussion and Analysis of

Financial Condition and Results of Operations (Continued)

I. RESULTS OF OPERATIONS (CONTINUED)

The Energy Group's operating profit was $4.5 million, compared with $8.3 million in the first quarter of 1996. Excluding the coal handling business' results and a gain from the reduction of the Company's ownership position in the Trinidad liquefaction joint venture from the 1996 results to form a comparative basis, the Group's operating profit increased $2.4 million, or 114% in the first quarter of fiscal 1997. The earnings increase reflected higher gas prices and greater availability of liquefied natural gas.

The Company's income tax rate for the first quarter was 36%, compared with a 37% rate for fiscal 1996.

II. CASH FLOWS AND LIQUIDITY

During the quarter, the Company generated $0.8 million of cash from operations. Working capital increased $44.6 million primarily due to business seasonality. Effective September 30, 1996, the Company sold its TUCO INC. subsidiary for $77 million. Accordingly, during the quarter, the Company received $35 million in cash, which included $8 million of working capital adjustments, and $50 million in the form of a debt repayment on Cabot's behalf from the respective buyer.

Capital expenditures totaled $58.6 million during the three months ended December 31, 1996. The Company expects to spend a total of $200 million to $225 million on capital projects during fiscal year 1997. The major components of the 1997 capital program include new carbon black capacity to support the contracts with U.S. tire manufacturers, Clean Air Act compliance, differentiated product manufacturing capabilities, new business expansion spending and normal plant maintenance spending.

During the quarter, the Company repurchased approximately 1,500,000 shares of common stock. These repurchases were funded with the proceeds from the sale of its TUCO INC. subsidiary and short term borrowings. At the end of the quarter, approximately 1,800,000 shares remained under the April 1996 repurchase authorization for 4,000,000 shares.

The Company's ratio of total debt (including short-term debt net of cash) to capital increased to 41% from 40% at the beginning of the three month period. On February 6, 1997, the Company issued $90 million of medium-term notes maturing from 2004 to 2011 with a weighted average interest rate of approximately 7%. The proceeds from the issuance were used to repay short-term debt.

During the quarter, the Company renegotiated its line of credit agreement. The facility was increased to $300 million from $250 million and was extended to January 3, 2002. Management expects cash from operations and present financing arrangements, including the Company's unused line of credit of $300 million, to be sufficient to meet the Company's cash requirements for the foreseeable future.

-10-

CABOT CORPORATION

Management's Discussion and Analysis of

Financial Condition and Results of Operations (Continued)

(Dollars in millions, except per share amounts)

UNAUDITED

                                                     Three Months Ended
                                                  ------------------------
                                                  12/31/96        12/31/95
                                                  --------        --------
Industry Segment Data

Sales:
Specialty Chemicals and Materials                  $ 340.2        $ 344.0
Energy                                                58.6           99.0
                                                   -------        -------
   Net sales                                       $ 398.8        $ 443.0
                                                   =======        =======

Operating profit:
Specialty Chemicals and Materials                  $  45.9        $  71.8
Energy                                                 4.5            8.3
                                                   -------        -------
   Total operating profit                             50.4           80.1

Interest expense                                      (9.7)          (9.4)
General corporate/other expenses                      (6.0)          (5.9)
                                                   -------        -------

Income before income taxes                            34.7           64.8
Provision for income taxes                           (12.5)         (24.0)
Equity in net income of affiliated companies           4.0            3.7
Minority interest                                     (1.1)          (1.1)
                                                   -------        -------

Net income                                            25.1           43.4

Dividends on preferred stock                          (0.8)          (0.9)
                                                   -------        -------

Income applicable to primary common shares         $  24.3        $  42.5
                                                   =======        =======

Income per common share:

   Primary                                         $  0.34        $  0.57
                                                   =======        =======
   Fully diluted                                   $  0.32        $  0.53
                                                   =======        =======

-11-

Part II. Other Information

Item 6. Exhibits and Reports on Form 8-K

(a) Exhibits

The exhibit numbers in the following list correspond to the number assigned to such exhibits in the Exhibit Table of Item 601 of Regulation S-K:

Exhibit
Number        Description
------        -----------
 4            Second Supplemental Indenture, dated as of January 31,
              1997, between Cabot Corporation and State Street
              Bank and Trust Company, Trustee, filed herewith.

11            Statement Regarding Computation of Per Share Earnings, filed herewith.

12            Statement Regarding Computation of Ratio of Earnings to Fixed Charges, filed herewith.

25            Statement of Eligibility under the Trust Indenture Act of 1939 of a Corporation
              Designated to Act as Trustee, filed herewith.

27            Financial Data Schedule, filed herewith. (Not included with printed copy of the Form 10-Q.)

(b) Reports on Form 8-K

No report on Form 8-K was filed by the Company during the three months ended December 31, 1996.

-12-

SIGNATURES

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 thereunto duly authorized.

CABOT CORPORATION

Date: February 14, 1997              /s/ Kenyon C. Gilson
                                     ------------------------------------------
                                     Kenyon C. Gilson
                                     Executive Vice President and
                                     Chief Financial Officer

Date: February 14, 1997              /s/ William T. Anderson
                                     ------------------------------------------
                                     William T. Anderson
                                     Acting Corporate Controller
                                     (Chief Accounting Officer)

-13-

EXHIBIT 4

SECOND SUPPLEMENTAL INDENTURE, dated as of January 31, 1997, between CABOT CORPORATION, a corporation duly organized and existing under the laws of the State of Delaware (herein called the "Company"), having its principal executive offices at 75 State Street, Boston, Massachusetts, and THE STATE STREET BANK AND TRUST COMPANY, a Massachusetts trust company (herein called the "Trustee"), having its principal corporate trust office at Two International Place, Boston, Massachusetts 02110.

RECITALS

WHEREAS, the Company has entered into an Indenture dated as of December 1, 1987 and supplemented by a First Supplemental Indenture dated June 17, 1992 (as the same may be modified by the Trust Indenture Reform Act of 1990, the "Indenture"), with The First National Bank of Boston, as the Trustee's predecessor, to provide for the issuance from time to time of the Company's Securities, to be issued in one or more series; and

WHEREAS, Section 9.01 of the Indenture provides, among other things, that the Company and the Trustee may enter into indentures supplemental to the Indenture to cure any ambiguity, omission, defect or inconsistency or to make other formal changes and to make any change that does not adversely affect the rights of any Securityholder; and

WHEREAS, the Trustee became the successor to The First National Bank of Boston, as Trustee under the Indenture, pursuant to Section 7.09 of the Indenture; and

WHEREAS, all conditions have been complied with, all actions have been taken and all things have been done which are necessary to make this Second Supplemental Indenture a valid and binding supplement to the Indenture.

NOW, THEREFORE, THIS SECOND SUPPLEMENTAL INDENTURE WITNESSETH:

For and in consideration of the premises and the purchase of the Securities by the holders thereof, it is mutually covenanted and agreed, for the equal and proportionate benefit of all holders of Securities, as follows:

Section 1. Definitions. Capitalized terms not defined herein shall have their associated meanings as defined in the Indenture.

Section 2. Successor Trustee. The Trustee succeeded The First National Bank of Boston, as Trustee under the Indenture, pursuant to Section 7.09 of the Indenture, with effect from and after October 2, 1995 (the "Effective Date").


Section 3. Incorporation of Indenture. From and after the date hereof, the Indenture, as supplemented and amended by this Second Supplemental Indenture, shall be read, taken and construed as one and the same instrument with respect to the Securities.

Section 4. Acceptance of Trust. The Trustee accepts the trusts created by the Indenture, from and after the Effective Date, as supplemented by this Second Supplemental Indenture, and agrees to perform the same upon the terms and conditions in the Indenture, as supplemented by this Second Supplemental Indenture.

Section 5. Counterparts. This Second Supplemental Indenture may be executed in any number of counterparts, each of which when so executed shall be deemed to be an original, but all such counterparts shall together constitute but one and the same instrument.

IN WITNESS WHEREOF, the parties hereto have caused this Second Supplemental Indenture to be duly executed, and their respective seals to be hereunto affixed and attested, all as of the date first above written.

CABOT CORPORATION

                                             BY:  /s/ Kenyon C. Gilson
                                                ----------------------
                                                    Kenyon C. Gilson,
                                                    Executive Vice President and
                                                    Chief Financial Officer

ATTEST:

/s/ Edith C. McGuinness
- -----------------------
Edith C. McGuinness
Assistant Secretary
                                             THE STATE STREET BANK AND
                                                 TRUST COMPANY, as Trustee

                                             BY: /s/ Henry W. Seemore
                                                 --------------------
                                                    Henry W. Seemore,
                                                    Assistant Vice President

ATTEST:


/s/ Eric J. Donaghey

- --------------------


EXHIBIT 11

CABOT CORPORATION AND CONSOLIDATED SUBSIDIARIES

STATEMENT REGARDING COMPUTATION OF PER SHARE EARNINGS

For the three month period ended December 31, 1996


(In thousands, except per share amounts)

                                                             Primary      Fully Diluted
                                                             --------     -------------
Shares of common stock outstanding at October 1, 1996,
   less treasury stock                                         71,589          71,589

Plus net weighted shares of treasury stock purchased             (692)           (692)

Plus common stock equivalents:

   Effect of convertible preferred stock conversion                             6,069
   Effect of equity incentive awards                            1,122           1,122
                                                             --------        --------
Weighted average shares outstanding                            72,019          78,088
                                                             ========        ========

Income applicable to common shares                           $ 24,293        $ 24,293

Dividends on preferred stock                                                      820

Preferred stock conversion compensation shortfall                                (511)
                                                             --------        --------
Earnings applicable to common shares                         $ 24,293        $ 24,602
                                                             ========        ========
Earnings per common share                                    $   0.34        $   0.32
                                                             ========        ========


EXHIBIT 12

CABOT CORPORATION AND CONSOLIDATED SUBSIDIARIES

STATEMENT REGARDING COMPUTATION OF RATIO OF EARNINGS TO FIXED CHARGES
(Dollars in thousands)

                                                 Three Months                            Years ended September 30
                                                    ended         ------------------------------------------------------------------
                                              December 31, 1996     1996          1995           1994         1993            1992
                                              -----------------   --------      --------      --------       --------       --------
Earnings:
   Pre-tax income from continuing operations        $34,744       $279,834      $256,029      $118,325       $ 67,900       $116,599
   Distributed income of affiliated companies         2,345         11,173        11,699         5,638          5,988          5,766

   Add fixed charges:
     Interest on indebtedness                         9,670         41,718        35,639        41,668         44,043         41,714
     Portion of rents representative of
       the interest factor                            1,209          4,837         5,515         5,879          4,838          4,933
                                                    -------       --------      --------      --------       --------       --------
  Income as adjusted                                $47,968       $337,562      $308,882      $171,510       $122,769       $169,012

Fixed charges:
  Interest on indebtedness                          $ 9,670       $ 41,718      $ 35,639      $ 41,668       $ 44,043       $ 41,714
  Capitalized interest                                   --             --            --            --             --          3,963
  Portion of rents representative of
     the interest factor                              1,209          4,837         5,515         5,879          4,838          4,933
                                                    -------       --------      --------      --------       --------       --------

  Total fixed charges                               $10,879       $ 46,555      $ 41,154      $ 47,547       $ 48,881       $ 50,610

  Ratio of earnings to fixed charges                   4.41           7.25          7.51          3.61           2.51           3.34
                                                    =======       ========      ========      ========       ========       ========


EXHIBIT 25

SECURITIES AND EXCHANGE COMMISSION
WASHINGTON, D.C. 20549


STATEMENT OF ELIGIBILITY UNDER THE
TRUST INDENTURE ACT OF 1939 OF A
CORPORATION DESIGNATED TO ACT AS TRUSTEE

Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) __

STATE STREET BANK AND TRUST COMPANY
(Exact name of trustee as specified in its charter)

              Massachusetts                                      04-1867445
    (Jurisdiction of incorporation or                         (I.R.S. Employer
organization if not a U.S. national bank)                   Identification No.)

225 Franklin Street, Boston, Massachusetts 02110


(Address of principal executive offices) (Zip Code)

John R. Towers, Esq. Senior Vice President and Corporate Secretary 225 Franklin Street, Boston, Massachusetts 02110 (617)654-3253


(Name, address and telephone number of agent for service)


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

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

                                75 STATE STREET
                               BOSTON, MA 02109
              (Address of principal executive offices) (Zip Code)


                             --------------------

CABOT CORPORATION SERIES A MEDIUM - TERM NOTES
(Title of indenture securities)


GENERAL

ITEM 1. GENERAL INFORMATION.

FURNISH THE FOLLOWING INFORMATION AS TO THE TRUSTEE:

(a) NAME AND ADDRESS OF EACH EXAMINING OR SUPERVISORY AUTHORITY TO WHICH IT IS SUBJECT.

Department of Banking and Insurance of The Commonwealth of Massachusetts, 100 Cambridge Street, Boston, Massachusetts.

Board of Governors of the Federal Reserve System, Washington, D.C., Federal Deposit Insurance Corporation, Washington, D.C.

ITEM 2. AFFILIATIONS WITH OBLIGOR.

IF THE OBLIGOR IS AN AFFILIATE OF THE TRUSTEE, DESCRIBE EACH SUCH

AFFILIATION.

The obligor is not an affiliate of the trustee or of its parent, State Street Boston Corporation.

(See note on page 6.)

ITEM 3. THROUGH ITEM 15. NOT APPLICABLE.

ITEM 16. LIST OF EXHIBITS.

LIST BELOW ALL EXHIBITS FILED AS PART OF THIS STATEMENT OF ELIGIBILITY.

1. A COPY OF THE ARTICLES OF ASSOCIATION OF THE TRUSTEE AS NOW IN EFFECT.

A copy of the Articles of Association of the trustee, as now in effect, is on file with the Securities and Exchange Commission as Exhibit 1 to Amendment No. 1 to the Statement of Eligibility and Qualification of Trustee (Form T-1) filed with the Registration Statement of Morse Shoe, Inc. (File No. 22-17940) and is incorporated herein by reference thereto.

2. A COPY OF THE CERTIFICATE OF AUTHORITY OF THE TRUSTEE TO COMMENCE BUSINESS, IF NOT CONTAINED IN THE ARTICLES OF ASSOCIATION.

A copy of a Statement from the Commissioner of Banks of Massachusetts that no certificate of authority for the trustee to commence business was necessary or issued is on file with the Securities and Exchange Commission as Exhibit 2 to Amendment No. 1 to the Statement of Eligibility and Qualification of Trustee (Form T-1) filed with the Registration Statement of Morse Shoe, Inc. (File No. 22-17940) and is incorporated herein by reference thereto.

3. A COPY OF THE AUTHORIZATION OF THE TRUSTEE TO EXERCISE CORPORATE TRUST POWERS, IF SUCH AUTHORIZATION IS NOT CONTAINED IN THE DOCUMENTS SPECIFIED IN PARAGRAPH (1) OR (2), ABOVE.

A copy of the authorization of the trustee to exercise corporate trust powers is on file with the Securities and Exchange Commission as Exhibit 3 to Amendment No. 1 to the Statement of Eligibility and Qualification of Trustee (Form T-1) filed with the Registration Statement of Morse Shoe, Inc. (File No. 22- 17940) and is incorporated herein by reference thereto.

4. A COPY OF THE EXISTING BY-LAWS OF THE TRUSTEE, OR INSTRUMENTS CORRESPONDING THERETO.

A copy of the by-laws of the trustee, as now in effect, is on file with the Securities and Exchange Commission as Exhibit 4 to the Statement of Eligibility and Qualification of Trustee (Form T-1) filed with the Registration Statement of Eastern Edison Company (File No. 33-37823) and is incorporated herein by reference thereto.

1

5. A COPY OF EACH INDENTURE REFERRED TO IN ITEM 4. IF THE OBLIGOR IS IN DEFAULT.

Not applicable.

6. THE CONSENTS OF UNITED STATES INSTITUTIONAL TRUSTEES REQUIRED BY
SECTION 321(b) OF THE ACT.

The consent of the trustee required by Section 321(b) of the Act is annexed hereto as Exhibit 6 and made a part hereof.

7. A COPY OF THE LATEST REPORT OF CONDITION OF THE TRUSTEE PUBLISHED PURSUANT TO LAW OR THE REQUIREMENTS OF ITS SUPERVISING OR EXAMINING AUTHORITY.

A copy of the latest report of condition of the trustee published pursuant to law or the requirements of its supervising or examining authority is annexed hereto as Exhibit 7 and made a part hereof.

NOTES

In answering any item of this Statement of Eligibility and Qualification which relates to matters peculiarly within the knowledge of the obligor or any underwriter for the obligor, the trustee has relied upon information furnished to it by the obligor and the underwriters, and the trustee disclaims responsibility for the accuracy or completeness of such information.

The answer furnished to Item 2. of this statement will be amended, if necessary, to reflect any facts which differ from those stated and which would have been required to be stated if known at the date hereof.

SIGNATURE

Pursuant to the requirements of the Trust Indenture Act of 1939, as amended, the trustee, State Street Bank and Trust Company, a corporation organized and existing under the laws of The Commonwealth of Massachusetts, has duly caused this statement of eligibility and qualification to be signed on its behalf by the undersigned, thereunto duly authorized, all in the City of Boston and The Commonwealth of Massachusetts, on the 29TH DAY OF JANUARY, 1997.

STATE STREET BANK AND TRUST COMPANY

By       /s/  Henry W. Seemore
         ------------------------------
         HENRY W. SEEMORE
         ASSISTANT VICE PRESIDENT

2

EXHIBIT 6

CONSENT OF THE TRUSTEE

Pursuant to the requirements of Section 321(b) of the Trust Indenture Act of 1939, as amended, in connection with the proposed issuance by CABOT CORPORATION of its CABOT CORPORATION SERIES A MEDIUM - TERM NOTES, we hereby consent that reports of examination by Federal, State, Territorial or District authorities may be furnished by such authorities to the Securities and Exchange Commission upon request therefor.

STATE STREET BANK AND TRUST COMPANY

                                      By:  /s/  Henry W. Seemore
                                           ----------------------------------
                                           HENRY W. SEEMORE
                                           ASSISTANT VICE PRESIDENT

DATED:  JANUARY 29,  1997

3

EXHIBIT 7

Consolidated Report of Condition of State Street Bank and Trust Company of Boston, Massachusetts and foreign and domestic subsidiaries, a state banking institution organized and operating under the banking laws of this commonwealth and a member of the Federal Reserve System, at the close of business December 31, 1995, published in accordance with a call made by the Federal Reserve Bank of this District pursuant to the provisions of the Federal Reserve Act and in accordance with a call made by the Commissioner of Banks under General Laws, Chapter 172, Section 22(a).

                                                                                Thousands of
ASSETS                                                                          Dollars

Cash and balances due from depository institutions:
         Noninterest-bearing balances and currency and coin ....                1,331,827
         Interest-bearing balances .............................                5,971,326
Securities .....................................................                6,325,054
Federal funds sold and securities purchased
         under agreements to resell in domestic offices
         of the bank and its Edge subsidiary ...................                5,436,994
Loans and lease financing receivables:
         Loans and leases, net of unearned income ....4,308,339
         Allowance for loan and lease losses .........   63,491
         Loans and leases, net of unearned income and allowances                4,244,848
Assets held in trading accounts ................................                1,042,846
Premises and fixed assets ......................................                  374,362
Other real estate owned ........................................                    3,223
Investments in unconsolidated subsidiaries .....................                   31,624
Customers' liability to this bank on acceptances outstanding ...                   57,472
Intangible assets ..............................................                   68,384
Other assets ...................................................                  670,058

Total assets ...................................................               25,558,018
                                                                               ==========

LIABILITIES

Deposits:
         In domestic offices ...................................                6,880,231
                  Noninterest-bearing ................4,728,115
                  Interest-bearing ...................2,152,116
         In foreign offices and Edge subsidiary ................                9,607,427
                  Noninterest-bearing ................   28,265
                  Interest-bearing ...................9,579,162
Federal funds purchased and securities sold under
         agreements to repurchase in domestic offices of
         the bank and of its Edge subsidiary ...................                5,913,969
Demand notes issued to the U.S. Treasury and Trading Liabilities                  530,406
Other borrowed money ...........................................                  493,191
Bank's liability on acceptances executed and outstanding .......                   57,387
Other liabilities ..............................................                  620,287
                                                                               ----------

Total liabilities ..............................................               24,102,898
                                                                               ----------

EQUITY CAPITAL
Common stock ...................................................                   29,176
Surplus ........................................................                  228,448
Undivided profits ..............................................                1,197,496
                                                                               ----------

Total equity capital ...........................................                1,455,120
                                                                               ----------

Total liabilities and equity capital ...........................               25,558,018
                                                                               ==========

4

I, Rex S. Schuette, Senior Vice President and Comptroller of the above named bank do hereby declare that this Report of Condition has been prepared in conformance with the instructions issued by the Board of Governors of the Federal Reserve System and is true to the best of my knowledge and belief.

Rex S. Schuette

We, the undersigned directors, attest to the correctness of this Report of Condition and declare that it has been examined by us and to the best of our knowledge and belief has been prepared in conformance with the instructions issued by the Board of Governors of the Federal Reserve System and is true and correct.

David A. Spina Marshall N. Carter Charles F. Kaye

5

ARTICLE 5


PERIOD TYPE 3 MOS
FISCAL YEAR END SEP 30 1996
PERIOD END DEC 31 1996
CASH 42,328
SECURITIES 0
RECEIVABLES 296,854
ALLOWANCES 4,813
INVENTORY 274,680
CURRENT ASSETS 638,370
PP&E 1,777,003
DEPRECIATION 836,036
TOTAL ASSETS 1,836,159
CURRENT LIABILITIES 612,740
BONDS 219,796
PREFERRED MANDATORY 0
PREFERRED 75,336
COMMON 135,550
OTHER SE 1,217,783
TOTAL LIABILITY AND EQUITY 1,836,159
SALES 398,825
TOTAL REVENUES 400,504
CGS 279,683
TOTAL COSTS 279,683
OTHER EXPENSES 22,747
LOSS PROVISION 0
INTEREST EXPENSE 9,670
INCOME PRETAX 34,744
INCOME TAX 12,507
INCOME CONTINUING 25,113
DISCONTINUED 0
EXTRAORDINARY 0
CHANGES 0
NET INCOME 25,113
EPS PRIMARY 0.34
EPS DILUTED 0.32