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                                                                          EX-10T


                         THE CHASE MANHATTAN CORPORATION
                        1987/82 LONG-TERM INCENTIVE PLAN


                             INSTRUMENT OF AMENDMENT



         WHEREAS, The Chase Manhattan Corporation has reserved the right to
amend The Chase Manhattan 1987/82 Long-Term Incentive Plan (the "Plan") and
desires to amend the Plan as set forth in this Instrument of Amendment;

         NOW, THEREFORE, the Plan is hereby amended as follows:

1. Section 6A(a) of the Plan is amended as follows:

         (a) The phrase "Except as provided in clause (3) below," shall be added
to the beginning of each of clauses (1) and (2) of Section 6A(a).

         (b) The following new clause (3) shall be added to the end of Section
6A(a):

                  (3) If an optionee's employment is terminated after the
         occurrence of an Approved Change in Control (as defined in Section
         6A(f)(iii) below), unless such termination is (i) for "Cause" (as
         defined in Section 6A(f) below), or (ii) by the optionee without Good
         Reason (as defined in Section 6A(e) below but excluding for this
         purpose subsection (i) thereof), the optionee's outstanding Options and
         Stock Appreciation Rights shall become immediately exercisable and the
         optionee shall have the right, subject to the provisions of Section
         4(d)(5) above, to exercise such Options and Stock Appreciation Rights,
         at any time within the twenty-four month period after such termination
         of employment. After the occurrence of an Approved Change in Control,
         any purported termination of an employee's employment (other than by
         reason of death) shall be communicated by a Notice of Termination (as
         defined in Section 6A(f) below) from CMC to the employee or from the
         employee to CMC, as the case may be.

2. Section 6A(b) of the Plan is amended as follows:

         (a) The following phrase shall be inserted immediately after the first
use of the phrase "Change in Control" in Section 6A(b):

         or a termination of employment under circumstances described in Section
         6A(a)(3) above that would entitle such employee to exercise immediately
         any options awarded to such employee

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         (b) The phrase "or such termination" shall be inserted immediately
after the second, third and fourth uses of the phrase "Change in Control" in
Section 6A(b).

3. Section 6A(d) is amended by adding the following new sentence to the end
thereof:


         For purposes of this Section 6A(d), the definition of "Change in
         Control" shall be that set forth in Section 6A(f) below except that the
         third sentence of Section 6A(f)(3) shall be ignored. The definition of
         "Good Reason" applicable to any Potential Change in Control related to
         any Approved Change in Control shall, for purposes of this Section
         6A(d), exclude subsection (i) of the definition of "Good Reason" set
         forth in Section 6(f)(7) hereof.

4. Section 6A(e) is amended by adding the following new sentence to the end
thereof:


         For purposes of this Section 6A(e), the definition of "Change in
         Control" shall be that set forth in Section 6A(f) below except that the
         third sentence of Section 6A(f)(3) shall be ignored.

5. Section 6A(f)(3) of the Plan is amended by inserting at the end thereof the
following:

         For purposes of the Plan, any Approved Change in Control shall not
         constitute a Change in Control. As used herein, the term "Approved
         Change in Control" means any Change in Control occurring by reason of
         or upon the occurrence of the transactions and events contemplated by
         the Merger Agreement. "Merger Agreement" means any agreement or plan of
         merger or consolidation between CMC and Chemical Banking Corporation
         that is approved by the Boards of Directors of CMC and Chemical Banking
         Corporation on or before September 30, 1995, as modified from time to
         time.

6. This Instrument of Amendment shall be effective as of August 25, 1995.



         IN WITNESS WHEREOF, The Chase Manhattan Corporation has executed this
Instrument of Amendment as of August 25, 1995.


                                                 THE CHASE MANHATTAN CORPORATION



                                                 By:  /s/ JOHN J. FARRELL
                                                    ----------------------------
                                                    John J. Farrell
                                                    Executive Vice President