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                                                                  Exhibit 4.5(d)
                                    THIRD SUPPLEMENTAL INDENTURE dated as of
                           January 30, 1997 (this "Supplemental Indenture"),
                           between J. P. MORGAN & CO. INCORPORATED, a
                           corporation duly organized and existing under the
                           laws of the State of Delaware (the "Company") and
                           FIRST TRUST OF NEW YORK, NATIONAL ASSOCIATION,
                           successor to Chemical Bank (formerly Manufacturers
                           Hanover Trust Company), a national banking
                           association, as Trustee (hereinafter called the
                           "Trustee", which term shall include any successor
                           trustee appointed pursuant to Article Six of the
                           Basic Indenture hereinafter referred to).

                  WHEREAS the Company and the Trustee have entered into an
Indenture, dated as of August 15, 1982, as amended by supplemental indentures,
including a First Supplemental Indenture, dated as of May 5, 1986, and a Second
Supplemental Indenture, dated as of February 27, 1996 (as so amended, the "Basic
Indenture"), providing for the issuance from time to time of one or more series
of Securities (as such term is defined in the Basic Indenture) evidencing
unsecured indebtedness of the Company;

                  WHEREAS the Company proposes to issue one or more series of
MEDS, as described in the Indenture, but the principal amount at Maturity with
respect to which is mandatorily exchangeable into Exchange Issuer Securities or,
at the option of the Company, payable in cash, in either case at an Exchange
Rate as described herein;

                  WHEREAS Sections 8.1(f) and (d) of the Basic Indenture provide
that without the consent of the Holders of Securities, the Company, when
authorized by a resolution of its Board of Directors, and the Trustee may enter
into one or more indentures supplemental to the Basic Indenture (a) to establish
the form or terms of Securities of any series as permitted by Sections 2.1 and
2.3 thereof and (b) to cure any ambiguity or to correct or supplement any
provision contained in the Basic Indenture or any supplemental indenture which
may be defective or inconsistent with any other provision of the Basic Indenture
or any supplemental indenture or to make such other provisions in regard to
matters or questions arising under the Basic Indenture or any supplemental
indenture as the Board of Directors may deem necessary or desirable and which
shall not materially and adversely affect the interests of the Holders of the
Securities;

                  WHEREAS the entry into this Supplemental Indenture by the
parties hereto is in all respects authorized by the provisions of the Basic
Indenture; and

                  WHEREAS all things necessary to make this Supplemental
Indenture a valid agreement of the Company in accordance with its terms have
been done.

                  NOW, THEREFORE, for and in consideration of the premises and
purchase of the Securities by the Holders thereof, it is mutually covenanted and
agreed, for the equal and proportionate benefit of all Holders, without
preference, priority or distinction of any of the Securities over any of the
others by reason of difference in series or priority in time of issuance,
negotiation or maturity thereof, or otherwise except as otherwise provided in
the Basic Indenture or this Supplemental Indenture, as follows:
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                                                                               2

                                   ARTICLE I

                        Amendments to the Basic Indenture

                  The Basic Indenture is amended as set forth below:

                  SECTION 1.01. Amendments to Authorize Additional Exchange Rate
Option. The Basic Indenture is hereby amended, solely with respect to one or
more series of Securities that consist of MEDS, as follows:

                  (a) By amending Section 1.1 to add new definitions thereto, in
the appropriate alphabetical sequence, as follows:

                  "Capped Participation Percentage", with respect to any
 issuance of MEDS, shall have the meaning set forth in the applicable
 Prospectus Supplement.

                  (b) By amending the second sentence of Section 13.1 to read as
follows:

         "The `Exchange Rate' with respect to each series of MEDS shall be equal
         to, as set forth in the applicable Prospectus Supplement and subject to
         adjustment as a result of certain dilution events relating to the
         Issuer Exchange Securities as provided for in Section 13.3, either (I)
         (a) if the Maturity Price (as defined below) is greater than or equal
         to the `Threshold Appreciation Price' (as set forth in the applicable
         Prospectus Supplement), a number of Exchange Issuer Securities equal to
         a fraction, the numerator of which is one and the denominator of which
         is the sum of one and the Conversion Premium, (b) if the Maturity Price
         is less than the Threshold Appreciation Price but is greater than the
         Initial Price, a fractional Exchange Issuer Security per MEDS so that
         the value of such fractional Exchange Issuer Security (determined at
         the Maturity Price) is equal to the Initial Price (such fractional
         share being calculated to the nearest 1/10,000th of a share or, if
         there is not a nearest 1/10,000th of a share, to the next highest
         1/10,000th of a share) and (c) if the Maturity Price is less than or
         equal to the Initial Price, one Exchange Issuer Security per MEDS, (II)
         (a) if the Maturity Price is less than or equal to the `Capped
         Appreciation Price' (as set forth in the applicable Prospectus
         Supplement), one Exchange Issuer Security per MEDS, and (b) if the
         Maturity Price is greater than the Capped Appreciation Price, a
         fractional Exchange Issuer Security per MEDS so that the value of such
         fractional Exchange Issuer Security (determined at the Maturity Price)
         is equal to the Capped Appreciation Price (calculated as above) or
         (III) the Exchange Rate, as otherwise defined in any Prospectus
         Supplement relating to an issuance of MEDS."

                  (c) By amending the first sentence of Section 13.3 to read as
follows:

         "Unless otherwise specified in any Prospectus Supplement relating to an
         issuance of MEDS, the Exchange Rate shall be subject to adjustment from
         time to time as follows:"

                  (d) By adding the following Section 13.7:

                  "SECTION 13.7. Tax Matters. The parties hereto hereby agree,
and each Holder of a MEDS issued on or after January 30, 1997, by its purchase
of a MEDS hereby agrees:
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                                                                               3

                  (i) to treat, for U.S. federal income tax purposes, each MEDS
         as a forward purchase contract to purchase Exchange Issuer Securities
         at Maturity (including as a result of acceleration or otherwise) (the
         "forward purchase contract characterization"), under the terms of which
         contract (a) at the time of issuance of the MEDS the Holder deposits
         irrevocably with the Company a fixed amount of cash equal to the
         purchase price of the MEDS to assure the fulfillment of the Holder's
         purchase obligation described in clause (c) below, which deposit will
         unconditionally and irrevocably be applied at Maturity to satisfy such
         obligation, (b) until Maturity the Company will be obligated to pay
         interest on such deposit at a rate equal to the stated rate of interest
         on the MEDS as compensation to the Holder for the Company's use of such
         cash deposit during the term of the MEDS, and (c) at Maturity such cash
         deposit unconditionally and irrevocably will be applied by the Company
         in full satisfaction of the Holder's obligation under the forward
         purchase contract, and the Company will deliver to the Holder the
         number of Exchange Issuer Securities that the Holder is entitled to
         receive at that time pursuant to the terms of the MEDS (subject to the
         Company's right to deliver cash in lieu of the Exchange Issuer
         Securities);

                  (ii) to treat, consistent with the above characterization, (x)
         amounts paid to the Company in respect of the original issue of a MEDS
         as allocable in their entirety to the amount of the cash deposit
         attributable to such MEDS, and (y) amounts denominated as interest that
         are payable with respect to the MEDS as interest payable on the amount
         of such deposit, includible annually in the income of the Holder as
         interest income in accordance with its method of accounting; and

                  (iii) to file all U.S. federal, state and local income and
         franchise tax returns consistent with the forward purchase contract
         characterization (unless required otherwise by an applicable taxing
         authority or notified to such effect by the Company)."

                                   ARTICLE II

                                 Miscellaneous

                  SECTION 2.01. Single Indenture. The Basic Indenture, as
supplemented and amended by this Supplemental Indenture and all other indentures
supplemental thereto, is in all respects ratified and confirmed, and the Basic
Indenture, this Supplemental Indenture and all indentures supplemental thereto
shall be read, taken and construed as one and the same instrument.

                  SECTION 2.02. Trust Indenture Act. If any provision hereof
limits, qualifies or conflicts with another provision hereof which is required
to be included in this Supplemental Indenture by any of the provisions of the
Trust Indenture Act, such required provision shall control.

                  SECTION 2.03. Successors and Assigns. All covenants and
agreements in this Supplemental Indenture by the Company shall bind its
successors and assigns, whether so expressed or not.
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                                                                               4

                  SECTION 2.04. Severability. In case any provision in this
Supplemental Indenture or in the Securities of any series shall be invalid,
illegal or unenforceable, the validity, legality and enforceability of the
remaining provisions (or of the other series of Securities) shall not in any way
be affected or impaired thereby.

                  SECTION 2.05. Third Party Rights. Nothing in this Supplemental
Indenture, expressed or implied, shall give to any Person, other than the
parties hereto and their successors hereunder, and the Holders of each series of
Securities any benefit or any legal or equitable right, remedy or claim under
this Supplemental Indenture.

                  SECTION 2.06. Applicable Law. This Supplemental Indenture and
each Security of any series shall be deemed to be a contract made under the laws
of the State of New York and this Supplemental Indenture and each such Security
shall be governed by and construed in accordance with the laws of the State of
New York.

                  SECTION 2.07. Defined Terms. All terms used in this
Supplemental Indenture not otherwise defined herein that are defined in the
Basic Indenture shall have the meanings set forth therein.

                  SECTION 2.08. Counterparts. This Supplemental Indenture may be
executed in any number of counterparts, each of which shall be an original; but
such counterparts shall together constitute but one and the same instrument.

                  SECTION 2.09. Responsibility of Company. The recitals
contained herein and in the Securities, except the certificate of authentication
of the Trustee thereon, shall be taken as statements of the Company, and the
Trustee assumes no responsibility for their correctness. The Trustee makes no
representations as to the validity or sufficiency of the Basic Indenture, this
Supplemental Indenture or of the Securities and shall not be accountable for the
use or application by the Company of the Securities or the proceeds thereof.
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                  SECTION 2.10. Headings. The headings used herein are for
convenience of reference only, are not part of this Supplemental Indenture and
are not to affect the construction of, or to be taken into consideration in
interpreting, this Supplemental Indenture.

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

                                            J. P. MORGAN & CO. INCORPORATED,


                                            by ________________________________
                                               Name:
                                               Title:


[Seal]

Attest:

____________________________
Name:
Title:


                                            FIRST TRUST OF NEW YORK, NATIONAL
                                            ASSOCIATION, as Trustee,



                                             by _______________________________
                                                Name:
                                                Title:
[Seal]

Attest:

____________________________
Name:
Title:
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                                                                               6

STATE OF NEW YORK  )
                   ) ss.:
COUNTY OF NEW YORK )

                  On the 30th day of January 1997, before me personally came
           to me known, who, being by me duly sworn, did depose and say that
he/she is a          of J. P. MORGAN & CO. INCORPORATED, one of the corporations
described in and which executed the foregoing instrument; that he/she knows the
seal of said corporation; that the seal affixed to said instrument is such
corporate seal; that it was so affixed by authority of the Board of Directors of
said corporation, and that he/she signed his/her name thereto by like authority.


                                                _______________________________
                                                Notary Public
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                                                                               7

STATE OF NEW YORK  )
                   ) ss.:
COUNTY OF NEW YORK )

                  On the 30th day of January 1997, before me personally came
           to me known, who, being by me duly sworn, did depose and say that
he/she is an Assistant Vice President of FIRST TRUST OF NEW YORK, NATIONAL
ASSOCIATION, one of the corporations described in and which executed the
foregoing instrument; that he/she knows the seal of said corporation; that the
seal affixed to said instrument is such corporate seal; that it was so affixed
by authority of the Board of Directors of said corporation, and that he/she
signed his/her name thereto by like authority.

                                                _______________________________
                                                Notary Public