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                                                                    EXHIBIT 4.12
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                           FIRST INDUSTRIAL, L.P.

                                   Issuer

                                     to

                      FIRST TRUST NATIONAL ASSOCIATION

                                   Trustee

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

                        Supplemental Indenture No. 4

                        Dated as of  March 26, 1998.

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

                                $100,000,000
                                     of
           6 1/2% Dealer remarketable securities due April 5, 2011

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        SUPPLEMENTAL INDENTURE NO. 4, dated as of March 26, 1998 (the
"Supplemental Indenture"), between FIRST INDUSTRIAL, L.P., a limited
partnership duly organized and existing under the laws of the State of Delaware
(herein called the "Operating Partnership"), and First Trust National
Association, a national organization duly organized and existing under the laws
of the United States of America, as Trustee (herein called the "Trustee").

                    RECITALS OF THE OPERATING PARTNERSHIP

        The Operating Partnership has heretofore delivered to the Trustee an
Indenture dated as of May 13, 1997 (the "Indenture"), a form of which has been
filed with the Securities and Exchange Commission under the Securities Act of
1933, as amended, as an exhibit incorporated by reference to the Operating
Partnership's Registration Statement on Form S-3 (Registration No. 333-43641),
providing for the issuance from time to time of Debt Securities of the
Operating Partnership (the "Securities").

        Section 301 of the Indenture provides for various matters with respect
to any series of Securities issued under the Indenture to be established in an
indenture supplemental to the Indenture.

        Section 901(7) of the Indenture provides for the Operating Partnership
and the Trustee to enter into an indenture supplemental to the Indenture to
establish the form or terms of Securities of any series as provided by Sections
201 and 301 of the Indenture.

        All the conditions and requirements necessary to make this Supplemental
Indenture, when duly executed and delivered, a valid and binding agreement in
accordance with its terms and for the purposes herein expressed, have been
performed and fulfilled.

           NOW, THEREFORE, THIS SUPPLEMENTAL INDENTURE WITNESSETH:

        For and in consideration of the premises and the purchase of each of
the series of Securities provided for herein by the Holders thereof, it is
mutually covenanted and agreed, for the equal and proportionate benefit of all
Holders of the Notes or of either series thereof, as follows:

                                 ARTICLE ONE


              RELATION TO SENIOR INDENTURE; DEFINITIONS

        SECTION 1.1.  Relation to Senior Indenture.

        This Supplemental Indenture constitutes an integral part of the
Indenture.

        SECTION 1.2.  Definitions.

        For all purposes of this Supplemental Indenture, except as otherwise
expressly provided for or unless the context otherwise requires:

        (1)   Capitalized terms used but not defined herein shall have the
    respective meanings assigned to them in the Indenture; and




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        (2)   All references herein to Articles and Sections, unless otherwise
    specified, refer to the corresponding Articles and Sections of this
    Supplemental Indenture.
        
        "Acquired Indebtedness" means Indebtedness of a Person (i) existing at
the time such Person becomes a Subsidiary or (ii) assumed in connection with
the acquisition of assets from such Person, in each case, other than
Indebtedness incurred in connection with, or in contemplation of, such Person
becoming a Subsidiary or such acquisition.  Acquired Indebtedness shall be
deemed to be incurred on the date of the related acquisition of assets from any
Person or the date the acquired Person becomes a Subsidiary.

        "Annual Service Charge" for any period means (i) the aggregate interest
expense for such period in respect of, and the amortization during such period
of any original issue discount of, Indebtedness of the Operating Partnership
and its Subsidiaries and the amount of dividends which are payable during such
period in respect of any Disqualified Stock and (ii) so long as First
Securities, L.P. ("Securities, L.P.") is a Subsidiary of the Operating
Partnership, distributions which are payable during such period in respect of
any preference equity interests of Securities, L.P.

        "Base Rate" means 5.67%.                      

        "Business Day" means any day, other than a Saturday or Sunday, or a day
on which banking institutions in the City of New York or the City of Chicago
are authorized or obligated by law, regulation or executive order to close.

        "Capital Stock" means, with respect to any Person, any capital stock  
(including preferred stock), shares, interests, participations or other
ownership interests (however designated) of such Person and any rights (other
than debt securities convertible into or exchangeable for corporate stock),
warrants or options to purchase any thereof.

        "Comparable Treasury Issue" means the United States Treasury security
selected by the Remarketing Dealer as having an actual maturity on the
Determination Date (or the United States Treasury securities selected by the
Remarketing Dealer to derive an interpolated maturity on such Determination
Date) comparable to the remaining term of the Drs.

        "Comparable Treasury Price" means (a) the offer price for the
Comparable Treasury Issue (expressed as a percentage of its principal amount)
on the Determination Date, as set forth on Telerate Page 500, adjusted to
reflect settlement on the Remarketing Date if prices quoted on Telerate Page
500 are for settlement on any date other than the Remarketing Date, or (b) if
such page (or any successor page) is not displayed or does not contain such
offer prices on such Business Day, then (i) if the Remarketing Dealer obtains   
four or five Reference Treasury Dealer Quotations, the average of such
Reference Treasury Dealer Quotations for such Remarketing Date, after excluding
the highest and lowest of such Reference Treasury Dealer Quotations (unless
there is more than one highest or lowest quotation, in which case only one such
highest and/or lowest quotation shall be excluded), or (ii) if the Remarketing
Dealer obtains fewer than four such Reference Treasury Dealer Quotations, the
average of all such Reference Treasury Dealer Quotations.  The Remarketing


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Dealer shall have the discretion to select the time at which the Comparable  
Treasury Price is determined on the Determination Date.

        "Consolidated Income Available for Debt Service" for any period means
Earnings from Operations of the Operating Partnership and its Subsidiaries plus
amounts which have been deducted, and minus amounts which have been added, for
the following (without duplication): (i) interest on Indebtedness of the
Operating Partnership and its Subsidiaries, (ii) provision for taxes of the
Operating Partnership and its Subsidiaries based on income, (iii) amortization
of debt discount, (iv) provisions for gains and losses on properties and
property depreciation and amortization, (v) the effect of any noncash charge
resulting from a change in accounting principles in determining Earnings from
Operations for such period, (vi) amortization of deferred charges and (vii)
interest income related to investments irrevocably deposited with an agent of
the Operating Partnership or any of its Subsidiaries, as the case may be, for
the purpose of defeasing any indebtedness or any other obligation (whether
through a covenant defeasance or otherwise) pursuant to the terms of such
indebtedness or other obligation or the terms of any instrument creating or
evidencing it.

        "Corporate Trust Office" means the office of the Trustee at which, at
any particular time, its corporate trust business shall be principally
administered, which office at the date hereof is located at One Illinois
Center, 111 East Wacker Drive, Suite 3000, Chicago, Illinois 60601.

        "Disqualified Stock" means, with respect to any Person, any Capital
Stock of such Person which by the terms of such Capital Stock (or by the terms
of any security into which it is convertible or for which it is exchangeable or
exercisable), upon the happening of any event or otherwise (i) matures or is
mandatorily redeemable, pursuant to a sinking fund obligation or otherwise
(other than Capital Stock which is redeemable solely in exchange for Capital
Stock which is not Disqualified Stock or the maturity price or redemption price
of which may, at the option of such Person, be paid in Capital Stock which is
not Disqualified Stock), (ii) is convertible into or exchangeable or
exercisable for Indebtedness or Disqualified Stock or (iii) is redeemable at
the option of the holder thereof, in whole or in part (other than Capital Stock
which is redeemable solely in exchange for Capital Stock which is not
Disqualified Stock or the redemption price of which may, at the option of such
Person, be paid in Capital Stock which is not Disqualified Stock), in each case
on or prior to the Stated Maturity Date of the Drs.

        "Determination Date" has the meaning specified in Section 2.6(a)
hereof.

        "Dollar Price" means the discounted present value to the Remarketing
Date of the cash flows on a bond (x) with a principal amount equal to the
aggregate principal amount of the initially issued Drs., (y) maturing on the    
Stated Maturity Date and (z) bearing interest from the Remarketing Date,
payable semi-annually (assuming a 360-day year consisting of twelve 30-day
months) on the interest payment dates of the Drs. at a rate equal to the Base
Rate, using a discount rate equal to the Treasury Rate.

        "Drs." has the meaning specified in Section 2.1 hereof.

        "DTC" means The Depository Trust Company or its successor.



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        "Earnings from Operations" for any period means net income excluding
gains and losses on sales of investments, extraordinary items and property
valuation losses, net as reflected in the financial statements of the Operating
Partnership and its Subsidiaries for such period determined on a consolidated
basis in accordance with GAAP (except that for purposes hereof, each Subsidiary
of the Operating Partnership shall be treated as if such Subsidiary were a
subsidiary under GAAP).

        "Encumbrance" means any mortgage, lien, charge, pledge, encumbrance or 
security interest of any kind; provided, however, that the term "Encumbrance"   
shall not include any mortgage, lien, charge, pledge or security interest
securing any indebtedness or any other obligation which has been defeased
(whether a covenant defeasance or otherwise) pursuant to the terms of such
indebtedness or other obligation or the terms of any instrument creating or
evidencing it.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended,
and the rules and regulations promulgated thereunder by the Commission.

        "GAAP" means generally accepted accounting principles as used in the
United States applied on a consistent basis as in effect from time to time;
provided that solely for purposes of any calculation required by the financial
covenants contained herein, "GAAP" shall mean generally accepted accounting
principles as used in the United States on the date hereof, applied on a
consistent basis.

        "Indebtedness" of the Operating Partnership or any of its Subsidiaries
means any indebtedness of the Operating Partnership or any of its Subsidiaries,
whether or not contingent, in respect of (a) borrowed money or evidenced by
bonds, notes, debentures or similar instruments whether or not such
indebtedness is secured by any Encumbrance existing on property owned by the
Operating Partnership or any of its Subsidiaries, (b) indebtedness for borrowed
money of a Person other than the Operating Partnership or a Subsidiary of the
Operating Partnership which is secured by any Encumbrance existing on property
owned by the Operating Partnership or any of its Subsidiaries, to the extent of
the lesser of (x) the amount of indebtedness so secured and (y) the fair market
value of the property subject to such Encumbrance, (c) the reimbursement
obligations, contingent or otherwise, in connection with any letters of credit
actually issued or amounts representing the balance deferred and unpaid of the
purchase price of any property or services, except any such balance that
constitutes an accrued expense or trade payable, and all conditional sale
obligations or obligations under any title retention agreement, (d) the
principal amount of all obligations of the Operating Partnership or any of its
Subsidiaries with respect to redemption, repayment or other repurchase of any
Disqualified Stock, (e) any lease of property by the Operating Partnership or
any of its Subsidiaries as lessee which is reflected on the Operating
Partnership's consolidated balance sheet determined in accordance with GAAP
(except that for the purposes hereof, each Subsidiary of the Operating
Partnership shall be treated as if such Subsidiary were a subsidiary under
GAAP) as a capitalized lease, or (f) interest rate swaps, caps or similar
agreements and foreign exchange contracts, currency swaps or similar
agreements, and (ii) the liquidation preference on any issued and outstanding
preferred equity interests of Securities, L.P., to the extent, in the case of
items of indebtedness under (I)(a) through (c) above, that any such items
(other than letters of credit) would appear as a liability on the Operating
Partnership's consolidated balance sheet determined in accordance with GAAP
(except that for the purposes hereof, each Subsidiary of the Operating
Partnership shall 


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be treated as if such Subsidiary were a subsidiary under GAAP), and also
includes, to the extent not otherwise included, any obligation by the Operating
Partnership or any of its Subsidiaries to be liable for, or to pay, as obligor,
guarantor or otherwise (other than for purposes of collection in the ordinary
course of business), Indebtedness of another Person (other than the Operating
Partnership or any of its Subsidiaries) (it being understood that Indebtedness
shall be deemed to be incurred by the Operating Partnership or any of its
Subsidiaries whenever the Operating Partnership or such Subsidiary shall
create, assume, guarantee or otherwise become liable in respect thereof)
provided, however, that the term "Indebtedness" shall not include any
indebtedness or any other obligation that has been defeased (whether a covenant
defeasance or otherwise) pursuant to the terms of such indebtedness or other
obligation or the terms of any instrument creating or evidencing it.
        
        "Interest Payment Date" shall have the meaning set forth in Section
2.3.

        "Notification Date" shall have the meaning specified in Section 2.6(a).

        "Principal Repayment Date" means the date on which all principal and 
interest in respect of the Drs. would have been payable to a holder if such
redemption had not been made, namely (i) in the case of a redemption of Drs. at
any time prior to the Remarketing Date, the Remarketing Date, and (ii) in the
case of a redemption of Drs. at any time after the Remarketing Date, the Stated
Maturity Date.

        "Reference Corporate Dealer" means J.P. Morgan Securities Inc. and four
other leading dealers of publicly-traded debt securities of the Operating
Partnership acceptable to J.P. Morgan Securities Inc. and the Operating
Partnership.

        "Reference Treasury Dealer" means a primary U.S. Government securities
dealer in The City of New York (which may include the Remarketing Dealer)
selected by the Remarketing Dealer.

        "Reference Treasury Dealer Quotations" means, with respect to each
Reference Treasury Dealer, the offer price for the Comparable Treasury Issue
(expressed in each case as a percentage of its principal amount) for settlement
on the Remarketing Date, quoted in writing to the Remarketing Dealer by such
Reference Treasury Dealer by 3:30 p.m., New York City time, on the
Determination Date.



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        "Regular Record Date" shall have the meaning specified in Section 2.3.

        "Remarketing Agreement" means the Remarketing Agreement dated as of
March , 1998 between the Operating Partnership and J.P. Morgan Securities Inc.,
as Remarketing Dealer, as such agreement may be amended from time to time.

        "Remarketing Date" shall have the meaning specified in Section 2.3
hereof.

        "Remarketing Dealer" means J.P. Morgan Securities Inc. or its successor
and assigns under the Remarketing Agreement.

        "Stated Maturity Date" should have the meaning specified in Section
2.3.

        "Subsidiary" means, (i) with respect to any Person, any corporation,
partnership or other entity of which a majority of (a) the voting power of the
voting equity securities or (b) the outstanding equity interests of which are
owned, directly or indirectly, by such Person and (ii) with respect to the
Operating Partnership, Securities, L.P., so long as the Operating Partnership
owns, directly or indirectly, a majority of the outstanding non-preference
equity interests thereof.  For the purposes of this definition, "voting equity
securities" means equity securities having voting power for the election of
directors, whether at all times or only so long as no senior class of security
has such voting power by reason of any contingency.

        "Telerate Page 500" means the display designated as "Telerate Page 500"
on Dow Jones Markets Limited (or such other page as may replace Telerate Page
500 on such service) or such other service displaying the offer price specified
in clause (a) of the definition of Comparable Treasury Price, as may replace
Dow Jones Markets Limited.

        "Total Assets" as of any date means the sum of (i) the Undepreciated
Real Estate Assets and (ii) all other assets of the Operating Partnership and
its Subsidiaries determined in accordance with GAAP (except that for the
purposes hereof, each Subsidiary of the Operating Partnership shall be treated
as if such Subsidiary were a subsidiary under GAAP), but excluding accounts
receivable and intangibles; provided, however, that the term "Total Assets"
shall not include any assets which have been deposited in trust to defease any
indebtedness or any other obligation (whether through a covenant defeasance or
otherwise) pursuant to the terms of such indebtedness or other obligation or
the terms of any instrument creating or evidencing it.

        "Total Unencumbered Assets" means the sum of (i) those Undepreciated
Real Estate Assets not subject to an Encumbrance for borrowed money and (ii)
all other assets of the Operating 

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Partnership and its Subsidiaries not subject to an Encumbrance for borrowed
money, determined in accordance with GAAP (except that for the purposes hereof,
each Subsidiary of the Operating Partnership shall be treated as if such
Subsidiary were a subsidiary under GAAP), but excluding accounts receivable and
intangibles; provided, however, that the term "Total Unencumbered Assets" shall
not include any assets which have been deposited in trust to defease any
indebtedness or any other obligation (whether through a covenant defeasance or
otherwise) pursuant to the terms of such indebtedness or other obligation or
the terms of any instrument creating or evidencing it.
        
        "Treasury Rate" means the annual rate equal to the semi-annual
equivalent yield to maturity or interpolated (on a 30/360 day count basis)
yield to maturity on the Determination Date of the Comparable Treasury Issue
for value on the Remarketing Date, assuming a price for the Comparable Treasury
Issue (expressed as a percentage of its principal amount) equal to the
Comparable Treasury Price.

        "Undepreciated Real Estate Assets" as of any date means the cost
(original cost plus capital improvements) of real estate assets of the
Operating Partnership and its Subsidiaries on such date, before depreciation
and amortization, determined on a consolidated basis in accordance with GAAP
(except for the purposes hereof, each Subsidiary of the Operating Partnership
shall be treated as if such Subsidiary were a subsidiary under GAAP).

        "Unsecured Indebtedness" means Indebtedness which is not secured by any
Encumbrance upon any of the properties of the Operating Partnership or any of
its Subsidiaries.

                                 ARTICLE TWO

                                      
                          THE  SERIES OF SECURITIES

        SECTION 2.1.  Title of the Securities.

        There shall be Securities designated the "6 1/2% Dealer remarketable
securities due April 5, 2011" (the "Drs.")

        SECTION 2.2.  Limitation on Aggregate Principal Amount.

        The aggregate principal amount of the Drs. shall be limited to
$100,000,000, and, except as provided in this Section and in Section 306 of the
Indenture, the Operating Partnership shall not execute and the Trustee shall
not authenticate or deliver Drs. in excess of such aggregate principal amount.

        Nothing contained in this Section 2.2 or elsewhere in this Supplemental
Indenture, or in the Drs., is intended to or shall limit execution by the
Operating Partnership or authentication or delivery by the Trustee of Drs.
under the circumstances contemplated by Sections 303, 304, 305, 306, 906, 1107
and 1305 of the Indenture.



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<PAGE>   9

        SECTION 2.3.  Interest and Interest Rates; Maturity Date of Drs.

        The Drs. will bear interest from March 31, 1998 or from the immediately
preceding Interest Payment Date to which interest has been paid or duly
provided for, payable semi-annually in arrears on April 5 and October 5 of each
year, commencing October 5, 1998  (each, an "Interest Payment Date"), to the
Persons in whose name such Drs. are registered on the fifteenth calendar
(whether or not a Business Day), immediately preceding the related Interest
Payment Date (each, a "Regular Record Date").  Interest will be computed on the
basis of a 360-day year comprised of twelve 30-day months.  The interest so
payable on any Drs. which is not punctually paid or duly provided for on any
Interest Payment Date shall be payable to the Person in whose name such Drs. is
registered on the relevant Regular Record Date, at the close of business by
notice by or on behalf of the Operating Partnership to the holders of the Drs.,
mailed by first class mail not less than 15 days prior to the Regular Record
Date to their last address as they shall appear upon the Securities Register
not less than five days preceding the date of payment.  Payment may be made by
check mailed to the holder's address as it appears on the Securities Register.

        The Drs. will bear interest at the rate of 6 1/2% per annum to April 5,
2001 (the "Remarketing Date").  If pursuant to the Remarketing Agreement, the
Remarketing Dealer elects to remarket the Drs., then except as otherwise
provided (i) the Drs. shall be subject to mandatory tender to the Remarketing
Dealer at 100% of the principal amount thereof for remarketing on the
Remarketing Date subject to the terms and conditions provided for in Section
2.5 herein and (ii) on and after the Remarketing Date, the Drs. shall bear
interest at a rate determined by the Remarketing Dealer in accordance with the
procedures set forth in Section 2.6 herein.

        If any Interest Payment Date or the Stated Maturity Date falls on a day
that is not a Business Day, the required payment shall be made on the next
Business Day as if it were made on the date such payment was due and no
interest shall accrue on the amount so payable for the period from and after
such Interest Payment Date or Stated Maturity Date, as the case may be.

        The Drs. will mature on April 5, 2011 (the "Stated Maturity Date").

        SECTION 2.4.  Limitations on Incurrence of Indebtedness.       

        (a)   The Operating Partnership will not, and will not permit any of its
Subsidiaries to, incur any Indebtedness, other than intercompany Indebtedness
(representing Indebtedness to which the only parties are the Operating
Partnership and any of its Subsidiaries (but only so long as such Indebtedness
is held solely by any of the Operating Partnership and any of its
Subsidiaries)), if, immediately after giving effect to the incurrence of such
additional Indebtedness and the application of the proceeds thereof, the
aggregate principal amount of all outstanding Indebtedness of the Operating
Partnership and its Subsidiaries on a consolidated basis determined in
accordance with GAAP (except that for purposes hereof, each Subsidiary of the
Operating Partnership shall be treated as if such Subsidiary were a subsidiary
under GAAP) is greater than 60% of the sum of (without duplication) (i) the
Total Assets as of the end of the calendar quarter covered in the Operating
Partnership's Annual Report on Form 10-K or Quarterly Report on Form 10-Q, as
the case may be, most recently filed with the Commission (or, if such filing is
not permitted under the Ex-

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<PAGE>   10




change Act, with the Trustee) prior to the incurrence of such additional
Indebtedness and (ii) the purchase price of any real estate assets or mortgages
receivable acquired, and the amount of any securities offering proceeds
received (to the extent such proceeds were not used to acquire real estate
assets or mortgages receivable or used to reduce Indebtedness), by the
Operating Partnership or any of its Subsidiaries since the end of such calendar
quarter, including those proceeds obtained in connection with the incurrence of
such additional Indebtedness.
        
        (b)   The Operating Partnership will not, and will not permit any of its
Subsidiaries to, incur any Indebtedness if the ratio of Consolidated Income
Available for Debt Service to the Annual Service Charge for the four
consecutive fiscal quarters most recently ended prior to the date on which such
additional Indebtedness is to be incurred shall have been less than 1.5:1, on a
pro forma basis after giving effect thereto and to the application of the
proceeds therefrom, and calculated on the assumption that (i) such Indebtedness
and any other Indebtedness incurred by the Operating Partnership and its
Subsidiaries since the first day of such four-quarter period and the
application of the proceeds therefrom, including to refinance other
Indebtedness, had occurred at the beginning of such period; (ii) the repayment
or retirement of any other Indebtedness by the Operating Partnership and its
Subsidiaries since the first day of such four-quarter period had been repaid or
retired at the beginning of such period (except that, in making such
computation, the amount of Indebtedness under any revolving credit facility
shall be computed based upon the average daily balance of such Indebtedness
during such period); (iii) in the case of Acquired Indebtedness or Indebtedness
incurred in connection with any acquisition since the first day of such
four-quarter period, the related acquisition had occurred as of the first day
of such period with the appropriate adjustments with respect to such
acquisition being included in such pro forma calculation; and (iv) in the case
of any acquisition or disposition by the Operating Partnership or its
Subsidiaries of any asset or group of assets since the first day of such
four-quarter period, whether by merger, stock purchase or sale, or asset
purchase or sale, such acquisition or disposition or any related repayment of
Indebtedness had occurred as of the first day of such period with the
appropriate adjustments with respect to such acquisition or disposition being
included in such pro forma calculation.

        (c)   The Operating Partnership will not, and will not permit any of its
Subsidiaries to, incur Indebtedness secured by any Encumbrance upon any of the
property of the Operating Partnership or any of its Subsidiaries if,
immediately after giving effect to the incurrence of such additional
Indebtedness and the application of the proceeds thereof, the aggregate
principal amount of all outstanding Indebtedness of the Operating Partnership
and its Subsidiaries on a consolidated basis determined in accordance with GAAP
(except that for the purposes hereof, each Subsidiary of the Operating
Partnership shall be treated as if such Subsidiary were a subsidiary under
GAAP) which is secured by any Encumbrance on property of the Operating
Partnership or any of its Subsidiaries is greater than 40% of the sum of
(without duplication) (i) the Total Assets as of the end of the calendar
quarter covered in the Operating Partnership's Annual Report on Form 10-K or
Quarterly Report on Form 10-Q, as the case may be, most recently filed with the
Commission (or, if such filing is not permitted under the Exchange Act, with
the Trustee) prior to the incurrence of such additional Indebtedness and (ii)
the purchase price of any real estate assets or mortgages receivable acquired,
and the amount of any securities offering proceeds received (to the extent that
such proceeds were not used to acquire real estate assets or mortgages
receivable or used to reduce Indebtedness), by the Operating Partnership or any
of its Subsidiaries since the end of such calendar 

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<PAGE>   11
quarter, including those proceeds obtained in connection with the incurrence of
such additional Indebtedness.
        
        (d)   The Operating Partnership and its Subsidiaries may not at any time
own Total Unencumbered Assets equal to or less than 150% of the aggregate
outstanding principal amount of the Unsecured Indebtedness of the Operating
Partnership and its Subsidiaries on a consolidated basis determined in
accordance with GAAP (except that for the purposes hereof, each Subsidiary of
the Operating Partnership shall be treated as if such Subsidiary were a
subsidiary under GAAP).

        (e)   For purposes of this Section 2.4, Indebtedness shall be deemed to
be "incurred" by the Operating Partnership or a Subsidiary of the Operating
Partnership whenever the Operating Partnership or such Subsidiary shall create,
assume, guarantee or otherwise become liable in respect thereof.

        SECTION 2.5.  Mandatory Tender on Remarketing Date; Purchase and
                      Settlement.

        (a)   On a Business Day not later than five Business Days prior to the
Remarketing Date (the "Notification Date"), the Remarketing Dealer will notify
the Operating Partnership and the Trustee as to whether it elects to purchase
all of the outstanding Drs. on the Remarketing Date.  If, and only if, the
Remarketing Dealer so elects, the Drs. shall be subject to mandatory tender to
the Remarketing Dealer for purchase and remarketing on the Remarketing Date,
upon the terms and subject to the conditions described herein and in the
Remarketing Agreement.  The purchase price of the Drs. shall be equal to 100%
of the principal amount thereof.  No holder or beneficial owner of the Drs.
shall have any rights or claims under the Remarketing Agreement or against the
Operating Partnership or the Remarketing Dealer as a result of the Remarketing
Dealer not purchasing such Drs.

        (b)   The tender and settlement procedures with respect to the Drs. set
forth in the Remarketing Agreement shall be subject to modification, without
the consent of the holders of the Drs., to the extent required by DTC or, if
the book-entry system is no longer available for the Drs. at the time of the
remarketing, to the extent required to facilitate the tendering and remarketing
of Drs. in certificated form. In addition, the Remarketing Dealer may modify
the settlement procedures without the consent of the holders of the Drs. in
order to facilitate the settlement process.

        (c)   The Operating Partnership hereby agrees with the Trustee and the
holders of Drs. that (i) at all times, it will use its best efforts to maintain
the Drs. in book-entry form with DTC or any successor thereto and to appoint a
successor depository to the extent necessary to maintain the Drs. in book-entry 
form and (ii) it waives any discretionary right that it otherwise may have
under the Indenture to cause the Drs. to be issued in certificated form.

        SECTION 2.6.  Determination of Interest Rate to Maturity.

        (a)   The Remarketing Dealer shall determine the interest rate the Drs.
will bear from the Remarketing Date to the Stated Maturity Date (the "Interest
Rate to Maturity") on the third 

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<PAGE>   12



Business Day immediately preceding the Remarketing Date (the "Determination
Date") by soliciting by 3:30 p.m., New York City time, the Reference Corporate
Dealers (defined below) for firm, com mitted bids to purchase all outstanding
Drs. at the Dollar Price, and by selecting the lowest such firm, committed bid
(regardless of whether each of the Reference Corporate Dealers actually submits
a bid). Each bid shall be expressed in terms of the Interest Rate to Maturity
that the Drs. would bear (quoted as a spread over the Base Rate) based on the
following assumptions:
        
         (i)       the Drs. would be sold to the Reference Corporate Dealer on
    the Remarketing Date for settlement on the same day;

         (ii)      the Drs. would mature on the Stated Maturity Date; and

         (iii)     the Drs. would bear interest from the Remarketing Date at a
    stated rate equal to the Interest Rate to Maturity bid by such Reference
    Corporate Dealer, payable semi-annually on the interest payment dates for
    the Drs. 
    
         The Interest Rate to Maturity announced by the Remarketing Dealer as a
result of such process will be quoted to the nearest one hundred-thousandth
(0.00001) of one percent per annum and, absent manifest error, will be binding
and conclusive upon holders of the Drs., the Operating Partnership and the
Trustee.  The Remarketing Dealer shall have the discretion to select the time
at which the Comparable Treasury Price is determined on the Determination Date.

         (b)  The Remarketing Dealer shall have the right in its sole discretion
to  either (i) remarket the Drs. for its own account or (ii) sell the Drs. to
the Reference Corporate Dealer submitting the lowest firm, committed, bid
pursuant to this Section 2.6.  If two or more Reference Corporate Dealers
submit equivalent bids which constitute the lowest firm, committed bid, the
Remarketing Dealer may in its sole discretion elect to sell the Drs. to any
such Reference Corporate Dealer.

         (c)  If the Remarketing Dealer has elected to remarket the Drs. as
provided herein, then it shall notify the Operating Partnership, the Trustee
and DTC by telephone, confirmed in writing (which may include facsimile or
other electronic transmission), by 5:00 p.m., New York City time, on the
Determination Date of the Interest Rate to Maturity applicable to the Drs.
effective from and including the Remarketing Date.  


                                      11
<PAGE>   13

        SECTION 2.7.  Repurchase.                             

        If the Remarketing Dealer (i) does not elect to exercise its right to a
mandatory tender of the Drs., (ii) shall not have received by the required time
on the Determination Date any firm, committed bids to purchase all of the Drs.
in accordance with Section 2.6 of this Supplemental Indenture or (iii) for any
other reason does not purchase all of the Drs. on the Remarketing Date, then
the Operating Partnership shall repurchase on the Remarketing Date, at a price
equal to 100% of the principal amount of the Drs. plus all accrued interest, if
any, on the Drs. to (but excluding) the Remarketing Date, any Drs. that have
not been purchased by the Remarketing Dealer on the Remarketing Date.

        SECTION 2.8.  Redemption.

        If the Remarketing Dealer has elected to remarket the Drs. on the 
Remarketing Date, the Operating Partnership shall have the right to redeem the  
Drs., in whole but not in part, from the Remarketing Dealer on the Remarketing
Date at a redemption price equal to the greater of (i) 100% of the aggregate
principal amount of the Drs. and (ii) the Dollar Price, by giving written
notice of such redemption to the Remarketing Dealer

              (x) no later than the Business Day immediately prior to the
              Determination Date or
        
              (y) if fewer than three Reference Corporate Dealers submit firm,
              committed bids to the Remarketing Dealer on the Determination
              Date in accordance with Section 2.6 of this Supplemental
              Indenture, immediately after the deadline set by the Remarketing
              Dealer for receiving such bids has passed.
        
        In either such case, the Operating Partnership shall pay such
redemption price for the Drs. in same-day funds by wire transfer on the
Remarketing Date to an account designated by the Remarketing Dealer.

        Notice of any such redemption will be mailed at least 30 days but not
more than 60 days before the redemption date to each holder of the Drs. to be
redeemed.  Unless the Operating Partnership defaults in payment of the
redemption price, on and after the redemption date, interest will cease to
accrue on the Drs. or portions thereof called in connection with a redemption.
If less than all the Drs. are to be redeemed at the option of the Operating
Partnership, the Operating Partnership will notify the Trustee at least 45 days
prior to the redemption date (or such shorter period as is satisfactory to the
Trustee) of the aggregate principal amount of Drs. to be redeemed and their
redemption date.  The Trustee shall select, in such manner as it shall deem
fair and appropriate, the Drs. to be redeemed in whole or in part.  Drs. may be
redeemed in part in the minimum authorized denomination of the Drs. or in any
integral multiple thereof.



                                      12
<PAGE>   14



        SECTION 2.9.  Places of Payment.

        The Places of Payment where the Drs. may be presented or surrendered
for payment, where the Drs. may be surrendered for registration of transfer or
exchange and where notices and demands to and upon the Operating Partnership in
respect of the Drs. and the Indenture may be served shall be in (i) the Borough
of Manhattan, The City of New York, New York, and the office or agency for such
purpose shall initially be located at First  Trust National Association, 100
Wall Street, Suite 2000, New York, New York 10005 and (ii) the City of Chicago,
Illinois and the office or agency for such purpose shall initially be located
at First Trust National Association, One Illinois Center, 111 East Wacker
Drive, Suite 3000, Chicago, Illinois 60601.

        SECTION 2.10.  Method of Payment.
        
        Payment of the principal of and interest on the Drs. will be made at
the office or agency of the Operating Partnership maintained for that purpose
in the Borough of Manhattan, The City of New York (which shall initially be an
office or agency of the Trustee), in immediately available funds, in such coin
or currency of the United States of America as at the time of payment is legal
tender for payment of public and private debts; provided, however, that at the
option of the Operating Partnership, payments of principal and interest on the
Drs. (other than payments of principal and interest due on the Stated Maturity
Date) may be made (i) by check mailed to the address of the Person entitled
thereto as such address shall appear in the Security Register or (ii) by wire
transfer to an account maintained by the Person entitled thereto located within
the United States.

        SECTION 2.11.  Registered Securities; Global Form.

        The Drs. shall be issuable and transferable in fully registered form as
Registered Securities, without coupons in denominations of $1,000 and any
integral multiple thereof.  The Drs. shall each be issued in the form of one or
more permanent Global Securities.  The depository for the Drs. shall be DTC.
The Drs. shall not be issuable in definitive form except as provided in Section
305 of the Indenture.  The Drs. shall be substantially in the form attached as
Exhibit A hereto.

        SECTION 2.12.  Registrar and Paying Agent.

        The Trustee shall initially serve as Registrar and Paying Agent for the
Drs.

        SECTION 2.13.  Defeasance.

        The provisions of Sections 1402 and 1403 of the Indenture, together
with the other provisions of Article Fourteen of the Indenture, shall be
applicable to the Drs.  The provisions of Section 1403 of the Indenture shall
apply to the covenants set forth in Sections 2.4 and 2.15 of this Supplemental
Indenture.

        SECTION 2.14.  Acceleration of Maturity; Rescission and Annulment.


                                     13


<PAGE>   15

        The provisions of the first paragraph of Section 502 of the Senior
Indenture as applicable with respect to the Drs. shall be deemed to be amended
and restated in their entirety to read as follows:

        If an Event of Default with respect to the Securities at the time
Outstanding occurs and is continuing, then in every such case the Trustee or
the Holders of not less than 25% in principal amount of the Outstanding
Securities  may declare the principal (or, if any Securities are Original Issue
Discount Securities or Indexed Securities, such portion of the principal as may
be specified in the terms thereof) of, and the Make-Whole Amount, if any, on,
all the Securities to be due and payable immediately, by a notice in writing to
the Operating Partnership (and to the Trustee if given by the Holders), and
upon any such declaration such principal or specified portion thereof shall
become immediately due and payable.  If an Event of Default with respect to the
Securities of any series set forth in Section 501(6) of the Senior Indenture
occurs and is continuing, then in every such case all the Securities of that
series shall become immediately due and payable, without notice to the
Operating Partnership, at the principal amount thereof (or, if any Securities
are Original Issue Discount Securities or Indexed Securities, such portion of
the principal as may be specified in the terms thereof) plus accrued interest
to the date the Securities are paid plus the Make-Whole Amount, if any, on the
Securities.

        SECTION 2.15.  Provision of Financial Information.

        Whether or not the Operating Partnership is subject to Section 13 or
15(d) of the Exchange Act, the Operating Partnership will, to the extent
permitted under the Exchange Act, file with the Commission the annual reports,
quarterly reports and other documents which the Operating Partnership would
have been required to file with the Commission pursuant to such Section 13 or
15(d) if the Operating Partnership were so subject, such documents to be filed
with the Commission on or prior to the respective dates (the "Required Filing
Dates") by which the Operating Partnership would have been required so to file
such documents if the Operating Partnership were so subject.

        The Operating Partnership will also in any event (x) within 15 days of
each Required Filing Date (i) if the Operating Partnership is not then subject
to Section 13 or 15(d) of the Exchange Act, transmit by mail to all Holders of
the Drs., as their names and addresses appear in the Security Register, without
cost to such Holders, copies of the annual reports and quarterly reports which
the Operating Partnership would have been required to file with the Commission
pursuant to Section 13 or 15(d) of the Exchange Act if the Operating
Partnership were subject to such Sections and (ii) file with the Trustee copies
of annual reports, quarterly reports and other documents which the Operating
Partnership is required to file with the Commission or would have been required
to file with the Commission pursuant to Section 13 or 15(d) of the Exchange Act
if the Operating Partnership were subject to such Sections and (y) if filing
such documents by the Operating Partnership with the Commission is not
permitted under the Exchange Act, promptly upon written request and payment of
the reasonable cost of duplication and delivery, supply copies of such
documents to any prospective Holder.


                                      14
<PAGE>   16

        SECTION 2.16.  Waiver of Certain Covenants.

        Notwithstanding the provisions of Section 1009 of the Indenture, the
Operating Partnership may omit in any particular instance to comply with any
term, provision or condition set forth in Sections 1004 to 1008, inclusive, of
the Indenture, with Sections 2.4 and 2.15 of this Supplemental Indenture and
with any other term, provision or condition with respect to the Drs. (except
any such term, provision or condition which could not be amended without the
consent of all Holders of the Drs.), if before or after the time for such
compliance the Holders of at least a majority in principal amount of all
outstanding Drs., by Act of such Holders, either waive such compliance in such
instance or generally waive compliance with such covenant or condition.  Except
to the extent so ex pressly waived, and until such waiver shall become
effective, the obligations of the Operating Partnership and the duties of the
Trustee in respect of any such term, provision or condition shall remain in
full force and effect.

                                ARTICLE THREE


                           MISCELLANEOUS PROVISIONS
        
        SECTION 3.1.  Ratification of Indenture.

        Except as expressly modified or amended hereby, the Indenture continues
in full force and effect and is in all respects confirmed and preserved.

        SECTION 3.2.  Governing Law.                                    

        This Supplemental Indenture and each Drs. shall be governed by and
construed in accordance with the laws of the State of New York.  This
Supplemental Indenture is subject to the provisions of the Trust Indenture Act
of 1939, as amended, and shall, to the extent applicable, be governed by such
provisions.

        SECTION 3.3.  Counterparts.

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


                                      15
<PAGE>   17


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



                               FIRST INDUSTRIAL, L.P.


                               By:  First Industrial Realty Trust, Inc.,
                                    its general partner


                               By:___________________________________
                                  Name:
                                  Title:


                               FIRST TRUST NATIONAL ASSOCIATION,
                                  as Trustee


                               By:___________________________________
                                  Name:
                                  Title:


                               By:___________________________________
                                  Name:
                                  Title: