EXHIBIT 4-F
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                         LOAN REPAYMENT AGREEMENT
                         ------------------------

     This Loan Repayment Agreement ("Agreement") is made this 9th

day of November, 1995 by and between RIVERFRONT OFFICE PARK JOINT

VENTURE, a Massachusetts general partnership ("Maker"), with a

mailing address at c/o Darvel Realty Trust, One Main Street,

Cambridge, Massachusetts 02142 ("ROPJV") and TEACHERS INSURANCE

AND ANNUITY ASSOCIATION OF AMERICA, a New York corporation,

having a mailing address at 730 Third Avenue, New York, New York

10017 ("TIAA").

                         W I T N E S S E T H:
                         -------------------

     WHEREAS, ROPJV is the Maker of Mortgage Note No. 1 dated

August 4, 1983 in the original principal amount of $25,300,000.00

("Note No. 1") with a principal balance on January 1, 1993 of

$24,788,526.00 and on March 1, 1993 of $24,771,715.06, Mortgage

Note No. 2 dated August 4, 1983 in the original principal amount

of $1,200,000.00 ("Note No. 2") with a principal balance on

January 1, 1993 of $1,168,436.67 and on March 1, 1993 of

$1,167,387.83, Mortgage Note No. 3 dated December 19, 1984 in the

original principal amount of $2,700,000.00 ("Note No. 3") with a

principal balance on January 1, 1993 of $2,616,796.40 and on

March 1, 1993 of $2,614,101.49 and Mortgage Note No. 4 dated

August 28, 1990 in the original stated principal amount of

$5,800,000.00 (of which only $5,734,000.00 was advanced) ("Note

No. 4") with a principal balance on January 1, 1993 and on

                                 - 1 -




March 1, 1993 of $5,734,000.00 (hereinafter Note No. 1, Note

No. 2, Note No. 3 and Note No. 4 are collectively called

"Notes"), each payable to the order of TIAA and (a) secured by a

Security Agreement and Mortgage Deed dated August 4, 1983 from

ROPJV to TIAA recorded with the Middlesex County South Registry

of Deeds in Book 15156, Page 568 and filed with the Middlesex

South Registry District of the Land Court as Document No. 645106

with Certificate of Title No. 136418 with the Middlesex South

Registry District of the Land Court in Book 812, Page 68 as

supplemented by a First Supplement to Security Agreement and

Mortgage Deed dated December 5, 1984, recorded with the said

Registry of Deeds in Book 15927, Page 403 and filed with the said

Registry District of the Land Court as Document No. 673276 and by

a Second Supplement to Security Agreement and Mortgage Deed dated

August 28, 1990, recorded with said Registry of Deeds in

Book 20736, Page 547 and filed as Document No. 828398 with said

Registry District of the Land Court (hereinafter said Security

Agreement and Mortgage Deed as so supplemented is called

"Mortgage") constituting a first mortgage lien upon certain real

property located in the City of Cambridge, Country of Middlesex,

Commonwealth Of Massachusetts as therein more particularly

described (hereinafter called "Mortgaged Premises") and (b) by an

Assignment of Lessor's Interest in lease(s) from ROPHV to TIAA

dated August 4, 1983 duly recorded with the said Registry of

Deeds in Book 15156, Page 592 and filed with the said Registry

District of the Land Court as Document No. 645107 (hereinafter

called "Assignment"),

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     WHEREAS, ROPJV is unable to perform its financial

obligations under the Notes, Mortgage and Assignment and ROPJV

desires to restructure its debt to TIAA so as to increase the

total of the presently outstanding principal balances of the

Notes by the amount of accrued and unpaid interest for the year

1993, compounded monthly at the rate of six (6%) per cent per

annum which accrued and unpaid interest so compounded in the

amount of $1,753,452.24 is reconstituted as principal (the total

of the principal balances of the Notes and said reconstituted

interest outstanding from time to time and all amounts payable

with respect thereto are hereinafter referred to as "Loan"), to

modify the maturity date thereof, the interest payable thereunder

and certain other terms relating to the repayment of the debt as

more fully set forth herein and TIAA is willing to restructure

the Loan in accordance with the provisions hereinafter set forth,

     WHEREAS, ROPJV is the tenant under a certain Ground Lease

dated September 23, 1981 with the Trustees of Darvel Realty Trust

as Ground Lessor and ROPJV as ground Lessee as amended by

Amendment dated August 4, 1983, and by Amendment No. 2 to Ground

Lease dated as of November 9, 1995 (hereinafter said Ground Lease

as so amended is referred to as "Ground Lease") which Ground

Lease is the subject of a certain Subordination and Waiver of

Rent Agreement dated August 4, 1983, recorded with said Registry

of Deeds in Book 15157, Page 26 and filed with said Registry

District of the Land Court as document No. 645109 and noted on

Certificate of Title No. 136418, and

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     WHEREAS, ROPJV and TIAA for their mutual benefit are

desirous that the Loan be repaid in accordance with the terms and

provisions of this Agreement.

     NOW THEREFORE, in consideration of the Mortgaged Premises

and of TEN ($10.00) DOLLARS and other good and valuable

consideration paid by the parties hereto each to the other, the

receipt and sufficiency of which is hereby acknowledged, ROPJV

and TIAA for their mutual benefit agree as follows:

     (A)  ROPJV for value received, promises to pay to TIAA or

order, at 730 Third Avenue, New York, New York 10017 or at such

other place as the holder of the ROPJV Notes may designate in

writing the total amount of THIRTY-FOUR MILLION TWO HUNDRED

EIGHTY-SEVEN THOUSAND TWO HUNDRED FOUR and 38/100

($34,287,204.38) DOLLARS comprised of the total of the presently

outstanding principal balance of Note No. 1 in the amount of

$24,771,715.06, the presently outstanding principal balance of

Note No. 2 in the amount of $1,167,387.83, the presently

outstanding principal balance of Note No. 3 in the amount of

$ 2,614,101.49, and the presently outstanding principal balance of

Note No. 4 in the amount of $5,734,000.00.

     (B)  ROPJV, for the value received, promises to pay TIAA or

order, at 730 Third Avenue, New York, New York 10017 or such

other place as the holder of the ROPJV Notes and this Agreement

may, designate in writing the amount of $1,753,452.24 which

represents accrued and unpaid interest for 1993 compounded

monthly at the rate of six (6%) per cent per annum in the amount

of $1,753,452.24 is hereby constituted as principal.

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     (C)  ROPJV and TIAA agree that the amount of $36,040,656.62

being a total of the balances of the Notes in the amount of

$34,287,204.38 and the reconstituted interest in the amount of

$1,753,452.24 shall be repaid as a single consolidated amount in

accordance with the terms and provisions of this Agreement.  Any

references hereinafter made to principal or original principal

balance(s) from and after the date of this Agreement shall mean

said $36,040,656.62 and any portions thereof remaining

outstanding from time to time and said principal and all amounts

payable with respect thereto are sometimes referred to as Loan.

     (D)  ROPJV agrees to pay the Loan in lawful money of the

United States of America with interest thereon in accordance with

the terms and provisions of this Agreement and in furtherance

thereof ROPJV (herein called "Maker") and TIAA (hereinafter

together with all subsequent holders of the Notes called

"Holder") agree as follows:

     1.  Wherever the term Note hereinafter appears it shall

mean the Notes and this Agreement collectively; wherever the term

Mortgage hereinafter appears, it shall mean the Mortgage as

amended by the Third Supplement To Security Agreement and

Mortgage Deed of even date and delivery herewith by and between

ROPJV and TIAA, duly recorded with the said Registry of Deeds and

filed with the said Registry District of the Land Court; wherever

the term Assignment hereinafter appears, it shall mean the

Assignment as amended by the First Amendment to Assignment of

Lessor's Interest in Lease(s) of even date and delivery herewith

by and between ROPJV and TIAA duly recorded with the said

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Registry of Deeds and filed with the said Registry District of

the Land Court; whatever the term Escrow Agreement hereinafter

appears, it shall mean the Escrow Agreement of even date and

delivery herewith, by and between ROPJV, Keller Company, Inc.,

and TIAA; and wherever the term Loan Documents hereinafter

appears, it shall mean the Note, Mortgage, Assignment, Escrow

Agreement, the First Amendment to Subordination and Waiver of

Rent Agreement between the holder and Darvel Realty Trust of even

date and delivery herewith (hereinafter called "Rent Waiver

Agreement"), and any other document delivered to TIAA in

connection with the Loan.  Wherever the term Mortgaged Premises

is hereinafter used it shall mean the mortgaged premises

described in the Mortgage.

     2.  The Maker covenants, agrees and confirms that the total

of the outstanding principal balances of the Notes on March 1,

1993 was $34,287,204.38 and the reconstituted principal balances

of the Note as of January 1, 1994 and on the date hereof is

$36,040,656.62 and all said amounts are owed by the Maker to the

Holder without offset, counterclaim or other defense, that the

Maker is the owner of the leasehold estate and every other part

of the Mortgaged Premises, that the Maker shall perform all the

terms and covenants of the Maker in the Mortgage, Assignment and

Escrow Agreement and that there are no offsets, counterclaims or

other defenses to the obligations of Maker under this Agreement,

the Notes, Mortgage, Assignment, Escrow Agreement or any other of

the Loan Documents and that all of the provisions of the Loan

Documents are in full force and effect.

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     3.  Notwithstanding any inconsistent provisions in the

Notes, the payment terms of Note No. 1, Note No. 2, Note No. 3 and

Note No. 4 are amended and restated as hereinafter set forth in

this Agreement and the principal of the Loan in the amount of

$36,040,656.62 and interest thereon is to be paid as follows:

     3.1  Commencing on the first day of January, 1994.

Fixed Interest (as defined below) shall accrue on the principal

balances outstanding hereunder from time to time and said Fixed

Interest shall be paid by the Maker in arrears on the first day

of each month commencing on February 1, 1994 and on the first day

of each month thereafter through and including December 1, 2007.

     3.2  The then outstanding principal balance, any

accrued unpaid Fixed Interest, the Minimum Return (as defined

below), the Prepayment/Maturity Amount (as defined below) and any

other amounts payable under the Note, if not sooner paid, shall

be payable on the Maturity Date (as defined below).

     3.3  For purposes hereof, the following definitions

shall apply:

     (a)  APPRAISAL.  "Appraisal" means the written report

of an Appraiser which values the Mortgaged Premises at the amount

which a ready and willing buyer would pay to a ready and willing

seller (with neither being compelled to buy or sell) under then

current market conditions to buy the Mortgaged Premises as if it

were free and clear of all liens and debts and, if the Appraisal

is submitted in connection with the payment of the Loan on a

Prepayment Date or on the Maturity Date but not otherwise,

benefitted by the agreement that Basic Rent shall not accrue and

                                  -7-




need not be paid under the Ground Lease until November 30, 2026

(except as otherwise provided in the Rent Waiver Agreement) and

not subject to any diminution of value as a result or a Spill of

Hazardous Waste or Materials as such terms are defined in the

Mortgage.

     (b)  APPRAISED VALUE.  "Appraised Value" means the fair

market value of the Mortgaged Premises obtained by an Appraisal.

     (c)  APPRAISER.  "Appraiser" means an independent

M.A.I. appraiser licensed and having at least ten (10) years of

experience appraising commercial real estate similar to the

Mortgaged Premises in the Boston and Cambridge areas.

     (d)  APPROVED BUDGET.  "Approved Budget" means the

budget for the Mortgaged Premises for a calendar year submitted

by the Maker to the Holder ninety (90) days prior to the

commencement of said calendar year and approved by the Holder

pursuant to the Mortgage in which Approved Budget the Maker and

the Holder agree to the estimated amount of the Cash Flow, Net

Operation Income, Gross Receipts and Operating Expenses of the

Mortgaged Premises for the subject calendar year.  No change in

the original Approved Budget for a calendar year made during said

calendar year by agreement of the Maker and the Holder shall

affect or change the Coverage Interest Rate then payable or the

prior agreed estimated Cash Flow amount used to determine the

Coverage Interest Rate then payable.

     (e)  CASH FLOW.  "Cash Flow" means Net Operating Income

less Capital Expenditures, Tenant Improvement Costs, Leasing

                                 - 8 -




Inducement Amounts and Leasing Commission as those terms are

defined in the Escrow Agreement.

     (f)  COVERAGE INTEREST RATE.  The "Coverage Interest

Rate" shall be that rate of interest per annum which would be

paid by the payment to the Holder in twelve (12) equal monthly

installments during each calendar year commencing in 1998 of the

amount obtained by dividing the estimated Cash Flow set forth in

the original Approved Budget for said calendar year by 1.2,

provided, however, that the Coverage Interest Rate in a calendar

year shall not exceed that rate which would cause the Holder to

have received on a interest payment date a yield having an

Internal Rate of Return of eighteen and one-half (18-1/2%) per cent

per annum, assuming the payment on each interest payment date

during said year of the outstanding principal balance of the Loan

and taking into consideration all previous payments of Fixed

Interest.

     (g)  DISCOUNTED VALUE.  "Discounted Value" means the

amount of a payment under the Note received after January 1, 1993

discounted at a particular rate from date of actual receipt

thereof by the Holder to January 1, 1993.

     (h)  FIXED INTEREST.  "Fixed Interest" means, prior to

January 1, 1998, the amount of interest computed at the Minimum

Fixed Interest Rate and, after December 31, 1997, the greater of

the amount of interest computed at the Minimum Fixed Interest

Rate or the amount of interest computed at the Coverage Interest

Rate.

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     (i)  GROSS RECEIPTS.  "Gross Receipts" means the

aggregate of all the money and the fair-market value of all property

and any other rent, issues, income of whatsoever type and nature

derived from the Mortgage Premises for a calendar year and shall

include all fixed, minimum and guarantee rents, overage rents,

percentage or participation rents, and all rentals and receipts

from written or oral leases, licenses and concessions received

from the Mortgage Premises including all amounts received

pursuant to escalation provisions contained in any and all

occupancy leases (including all contributions by occupancy

tenants or others for real  estate taxes, property insurance

expenses and operating expenses), all rent insurance proceeds and

cancellation premiums, and any and all other payments, credits or

offsets received in the nature of rent or additional rent,

parking fees, storage income, deposits or prepayments of rent in

the nature of security which are forfeited by lessees making such

deposits or prepayments, and any and all income and revenue of a

nonrental nature but excluding insurance and condemnation

proceeds to the extent used for repair or restoration and applied

in accordance with the Mortgage and excluding any construction

management fees to the extent paid under any management agreement

previously approved in writing by the Holder, and including

interest and other investment income such as paid on the Reserve

Escrow Account and the Working Capital Escrow Account.

     (j)  INTERNAL RATE OF RETURN.  "Internal Rate of

Return" means that the percentage rate which when applied as of any

date results in the total of the Discounted Value of all payments

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made under the Note (which are in accordance with the terms of the

Note to be used to determine such rate) discounted monthly at

such percentage rate equalling the total of the original

principal balances on January 1, 1993.  For the purposes of the

foregoing computation, (i) all advances made pursuant to the Note

shall be considered made on January 1, 1993, except that the

amount of 1,753,452.24 of the accrued and unpaid interest

compounded monthly at six (6%) per cent per annum reconstituted

as principal in accordance with the terms of this Agreement shall

be consideration an advance made on January 1, 1994, and (ii) all

payments made on account of the Note shall be considered made at

such times after January 1, 1993 as such payments were actually

received by Holder.

     (k)  MATURITY DATE.  The "Maturity Date: means

December 31, 2007.

     (l)  MINIMUM FIXED INTEREST RATE.  The "Minimum Fixed

Interest Rate" shall be (i) six (6%) per cent per annum during

the period from and including January 1, 1994 through and

including December 31, 1997, (ii) seven (7%) per cent per annum

during the period from and including January 1, 1998 through and

including December 31, 1999, (iii) eight and one-quarter (8 1/4%)

per cent per annum during the period from and including

January 1, 2000 through and including December 31, 2002, and (iv)

nine (9%) per cent per annum during the period from and including

January 1, 2003 through and including December 31, 2007.

     (m)  MINIMUM IRR RATE.  "Minimum IRR Rate" means an

Internal Rate of Return compounded monthly of not less than nine

                                 -11-




(9%) per cent per annum if the Prepayment Date occurs during each

of the calendar years 1995 through 1997, ten (10%) per cent per

annum if the Prepayment Date occurs during each of the calendar

years 1998 through 2002 or ten and one-half (10 1/2%) per cent per

annum if the Prepayment Date occurs during each of the calendar

years 2003 through 2007 and on the Maturity Date.

     (n)  MINIMUM RETURN.  "Minimum Return" means the amount

which, when paid to the Holder and added to prior payments of

principal and Fixed Interest made by the Maker under the Note,

will cause the Holder to have received on a Prepayment Date or

the Maturity Date a yield having an Internal Rate of Return equal

to the Minimum IRR Rate effective on such Prepayment Date or the

Maturity Date.  The Residual Amount payable on a Prepayment Date

or on the Maturity Date shall not be used in calculating the

Minimum Return.

     (o)  NET OPERATING INCOME.  "Net Operating Income"

means Gross Receipts less Operating Expenses.

     (p)  OPERATING EXPENSES.  "Operating Expenses" means

amounts paid by Maker in a calendar year in the ordinary course

of the maintenance, operation and use of the Mortgaged Premises

in accordance with the amounts set forth in the line item

categories in the Approved Budget, including (i) payroll, fringe

benefits and statutory payroll taxes, (ii) charges for

electricity, gas, telephone, water, sewer, garbage, laundry,

extermination, elevator, alarm system for common areas and

security guard services and other utilities required under tenant

leases or by statute, (iii) charges for fuel and reasonable

                                 -12-





inventory purchased, (iv) sales, business and real estate taxes

and assessments, (v) premiums for insurance, (vi) costs of

replacements (excluding Tenant Improvement Costs and Capital

Expenditures, as defined in the Escrow Agreement), repairs,

maintenance and supplies, (vii) charges for promotion and

advertising, (viii) management fees of up to three and one-half

(3 1/2%) of Gross Receipts from the Mortgaged Premises (inclusive of

all off-site overhead charges) plus reimbursement for reasonable

and customary direct on-site expenses of the manager, but only to

the extent included in the Approved Budget for any fiscal year,

(ix) charges for audited financial statements delivered to Holder

pursuant to the Mortgage, (x) reasonable legal fees and expenses

incurred in connection with (A) the drafting of new leases and

lease amendments, (B) actions to collect rents owing and (C) tax

abatement proceedings, and (xi) ground rent to the extent payable

in accordance with the provisions of the Rent Waiver Agreement.

The following shall not be deemed to be Operating Expenses:  (1)

payments of principal and interest on any indebtedness, including

the Note, (2) refunds to tenants of security deposits, (3)

payment for Capital Expenditures, Tenant Improvements Costs,

Leasing Inducement Amounts and Leasing Commissions as those terms

are defined in the Escrow Agreement, unless previously consented

to in writing by Holder, (4) depreciation or other non-cash

items, (5) prepaid expenses which are not customarily prepaid in

the ordinary course of business, (6) management fees payable in

excess of those approved in subparagraph (viii), above, (7)

general overhead expenses in connection with the operation of the

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Mortgaged Premises, (8) costs of Appraisals (except as they

relate to bona-fide tax abatement proceedings), (9) any escrow or

reserve funds established by Holder in connection with the

Mortgaged Premises (including, without limitation, the Reserve

Escrow Account and the Working Capital Reserve Account, (10)

audit fees described in paragraph 67(c) of the Mortgage, and (11)

ground rent, except to the extent said rent is permitted to be

paid under the Rent Waiver Agreement.

     (q)  PREPAYMENT/MATURITY AMOUNT.  "Prepayment/Maturity

Amount" means the sum of the Minimum Return and the Residual

Amount (as defined in paragraph 4.1 hereof).

     (r)  PREPAYMENT DATE.  "Prepayment Date" means the date

of payment of all amounts due hereunder prior to the Maturity

Date, whether by voluntary prepayment or other wise and, in the

event of a foreclosure, the Prepayment Date shall be the date of

the foreclosure sale, whether the Holder (or a third party)

successfully bids in the Mortgaged Premises at such sale.

     (s)  RESERVE ESCROW ACCOUNT.  "Reserve Escrow Account"

means the separate segregated account for the exclusive use and

benefit of Mortgaged Premises established pursuant to the Escrow

Agreement as the Reserve Escrow Account.

     (t)  WORKING CAPITAL RESERVE ACCOUNT.  "Working Capital

Reserve Account" means the separate segregated account for the

exclusive use and benefit of the Mortgaged Premises established

pursuant to the Escrow Agreement as the Working Capital Reserve

Account.

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     (u)  YIELD ACHIEVEMENT VALUE.  "Yield Achievement

Value" means that the Appraised Value of the Mortgaged Premises

is an amount which, assuming prepayment of the Loan, would result

in the sums being payable to the Holder on said assumed

Prepayment Date under the Note resulting in a yield to the Holder

having at lease an Internal Rate of Return at the Minimum IRR

Rate.

     3.4  All the Net Operating Income remaining after the

payment to the Holder of Fixed Interest computed at the Minimum

Fixed Interest Rate or Coverage Interest Rate, as the case may

be, shall be paid by Maker to the Escrow Agent to be held and

disbursed by the Escrow Agent pursuant to the terms and

provisions of the Escrow Agreement.

     3.5  Commencing in the calendar year 1997 and

thereafter during the term of the Loan, in the event that the

amount in the Reserve Escrow Account exceeds the greater of

$1,500,000.00 or such higher sum which is estimated as needed for

the Mortgaged Premises in the Holder's reasonable opinion based

on current financial projections (such greater sum being

hereinafter called "Reserve Requirement") the Maker shall pay

directly to the Holder all Net Income in excess of

Fixed Interest payments made under the Note which payments shall

be applied to reduce the principal balance of the Loan without

penalty or premium and which payments to the Holder shall

continue so long as the Reserve Escrow Account amount exceeds the

amount of the Reserve Requirement.  Whatever the balance of the

Reserve Escrow Account exceeds the Reserve Requirement, the

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Holder may require any excess over the Reserve Requirement to be

paid by the Escrow Agent to the Holder to reduce the principal

balance of the Loan (without penalty or premium).

     3.6  If the Maker delivers to the Holder evidence

satisfactory to the Holder in Holder's sole and absolute discretion

that the Mortgaged Premises on a particular date have a Yield

Achievement Value on such date, then thereafter the payment by

the Maker each month of any Net Operating Income remaining after

the payments of the Fixed Interest at the Minimum Fixed Interest Rate

or Coverage Interest Rate, as the case may be, either under

paragraph 3.4 to the Escrow Agent or under paragraph 3.5 to the

Holder directly shall be suspended and such amounts shall be

retained by the Maker, but only so long as in Holder's sole

opinion the Mortgaged Premises have a Yield Achievement Value.

     3.7  If the Maker believes the Mortgaged Premises have

a Yield Achievement Value and desires that the payments under

paragraph 3.4 and paragraph 3.5 be suspended, the Maker may cause

to be delivered to the Holder an Appraisal of the Mortgaged

Premises at any time with a written notice to the holder that it

appears to the Maker that the Mortgaged Premises have attained a

Yield Achievement Value and the Maker desires that the monthly

payments under paragraph 3.4 and paragraph 3.5 be suspended.

Thereafter so long as the payments under paragraph 3.4 or

paragraph 3.5 are suspended, the Maker shall cause to be

delivered to the Holder on October 1 of each calendar year an

Appraisal of the Mortgaged Premises (except that such Appraisal

may be so-called less formal "desk appraisal" in each calendar

                                - 16 -




year except the years 1997, 1999, 2002 and 2007, provided said

"desk appraisal" is in all respects satisfactory to the Holder in

Holder's sole and absolute discretion).  In addition, the Holder

may obtain at Maker's expense out of Gross Receipts (with the

cost so paid to be added to the Approved Budget) an Appraisal of

the Mortgaged Premises whenever the Holder desires to ascertain

whether the Mortgaged Premises continue to have a Yield

Achievement Value.

     3.8  In the event that, subsequent to the suspension of

payments, the Mortgaged Premises at any time thereafter no longer

have a Yield Achievement Value then payments to the Escrow Agent

as described in paragraphs 3.4 and 3.5 shall immediately commence

again to be made by the Maker either to the Escrow Agent or to

the Holder as the case may be.

     3.9  All amounts of Net Operating Income in excess of

Fixed Interest not paid under the provision of paragraph 3.4 to

the Escrow Agent or under paragraph 3.5 to the Holder ("Excess

NOI") shall be used by the Maker for the payment of Operating

Expenses, Shortfalls, Tenant Improvement Costs, Capital

Expenditures, Leasing Commissions or Lease Inducement Amounts all

as defined in the Escrow Agreement before drawing amounts for the

payment of such items from the Escrow Accounts as defined in the

Escrow Agreement.  It is the intention of the Maker and the

Holder that the Excess NOI be available for use for the Mortgaged

Premises and the Maker agrees that no distribution (as a

Dividend, return of capital or the like) of Excess NOI shall be

made by the Maker.

                                 -17-




     4.  The Maker may pay the principal indebtedness in full

only, but not in part together with all unpaid Fixed Interest and

the Prepayment/Maturity Amount on any installment due date, upon

giving the Holder of the Note one hundred twenty (120) days prior

written notice of its intention to so prepay.  In addition to the

Fixed Interest, Maker hereby promises, covenants and agrees to

pay to Holder on the Prepayment Date or on the Maturity Date the

Prepayment/Maturity Amount which shall mean an amount equal to

the sum of the Minimum Return, if any, and the Residual Amount

(as defined below); provided, however, the amount of the

Prepayment/Maturity Amount which shall exceed that amount which

would cause the Holder on the Prepayment Date or on the Maturity

Date to have received a yield at an Internal Rate of Return on

the total principal balances of the Notes on January 1, 1993

increased by the amount of $1,753,452.24 advanced as of

January 1, 1994 and thereafter outstanding from time to time in

excess of twenty-four (24%) per cent, compounded monthly.

     4.1  RESIDUAL AMOUNT.  For the purposes

hereof, "Residual Amount" shall mean an amount equal to fifty

percent (50%) of the sum of (i) the amount by which the sum of

the amounts held in the Reserve Escrow Account and the Working

Capital Reserve Account on the Prepayment Date or on the Maturity

Date exceeds any portion thereof used to pay the Minimum Return

and (ii) the greater of (A) the sale proceeds from the actual

sale of the Mortgaged Premises, after deducting only (and then

only to the extent such sums are actually paid to Holder or, in

the case of commissions and closing costs, to a non-affiliated

                                 -18-




third party entitled thereto) the then outstanding principal

balance of the Note, the then unpaid Fixed Interest on the Note,

the Minimum Return, if any, and any third-party brokerage

commissions paid by Maker in connection with such sale and other

customary closing costs paid by Maker, but only to the extent all

such commissions and all such closing costs do not exceed three

percent (3%) of such sale proceeds, or (B) the Appraised Value

(less three percent (3%) for a closing cost adjustment and) after

deducting only (and then only to the extent such sums are

actually paid to Holder) the then outstanding principal balance

of the Note, the then unpaid Fixed Interest on the Note, and the

Minimum Return, if any.  The greater of the amount determined in

(ii) (A) or (ii) (B) of the immediately preceding sentence is

hereinafter called "Capital Proceeds".

     4.2  In order to determine the Residual Amount to be

paid to Holder or to determine that no Residual Amount is payable

hereunder, the Maker shall forward the following document to the

Holder, either simultaneously with the sending of the notice of

intention to prepay prior to one hundred twenty (120) days of the

Prepayment Date is hereinabove provided, or within one hundred

twenty (120) days of the Maturity Date, and as a condition

precedent to such notice being deemed to be effective, or within

thirty (30) days of acceleration of maturity after default:  (a)

an Appraisal of the Mortgaged Premises prepared by an Appraiser;

(b) if the Mortgaged Premises are being sold to a third party

simultaneously with such payment, the contract of sale, real

estate brokerage agreement (if deduction for a brokerage

                                 -19-




commission is being claimed), and a statement of all estimated

closing costs, with supporting data, for which deductions are

being claimed; and if the sale is not for a one hundred (100%)

per cent interest in the Mortgaged Premises, then the sales price

set forth in the contract of sale shall be projected as if 100%

of the Mortgaged Premises were being sold and such projection

shall be used for determining the amount due the Holder

hereunder; additionally, the sales price for the purpose of

determining the amount due the Holder hereunder shall include the

amount of all cash payments, deferred payments, debts assumed

(other than the debt evidenced by the Note which may not be

assumed) and the value of all assets, securities, interest and

other consideration received or receivable in connection with

such sale; (c) a current rent roll of the Mortgaged Premises,

supporting leases not previously furnished to the Holder, and a

certified statement of income and expenses for the twelve month

period immediately preceding the date of such notice setting

forth all the information necessary to do an Appraisal of the

Mortgaged Premises; a statement of all other estimated closing

costs, with supporting data, for which deductions are

anticipated; and (d) a true and correct statement from the Maker

calculating all amounts due the Holder hereunder.  A statement of

final closing costs, with supporting data, shall be furnished at

the time of payment of the Prepayment/Maturity Amount.

     4.3  The Maker shall promptly furnish the Holder with

all additional information that Holder may reasonably request.

If the Holder does not agree with any of the conclusions,

                                 -20-




calculations, computations, valuations or other information

supplied the Holder, the Holder shall notify the Maker in writing

within ninety (90) days of Maker's submissions.  If such

disagreement is over whether or not the sale is a bona fide arms

length transaction limited to the Mortgaged Premises and

reflecting full value, or the amount of the Appraised Value of

the Mortgaged Premises, the Holder shall furnish the Maker an

Appraisal in conformity to the standards imposed on the Maker

with respect to an appraisal.  If the two Appraisals differ by

ten (10%) per cent or less the Appraised Value of the Mortgaged

Premises for the purposes of the Note shall be the average

valuation of the two Appraisals.  If the difference is greater

than ten (10%) per cent, either party shall have the right to

require that a third independent Appraiser, mutually satisfactory

to both the Maker or the Holder, be selected to appraise the

Mortgaged Premises.  Such third Appraiser shall render his report

within thirty (30) days of appointment, which report must not set

a valuation lower than the lowest valuation of the Appraisals

previously submitted nor higher than the highest valuation of the

appraisals previously submitted.  The valuations set forth in all

three Appraisals shall be aggregated and the Appraised Value of

the Mortgaged Premises shall be deemed to be the average of all

such appraisals.  Each party shall pay its own Appraiser, and the

parties shall each pay one-half of the cost of any third

Appraiser.  If the Maker does not in the time required supply an

Appraisal from an Appraiser meeting the qualifications in item

(a) of the immediate preceding paragraph, then the Holder may

                                 -21-




obtain such an Appraisal and the Maker agrees than any such

Appraisal obtained by and satisfactory to the Holder shall be the

Appraisal used in determining the amounts due the Holder

hereunder.  If the privilege to prepay is not exercised, the then

outstanding principal balance together with any unpaid Fixed

Interest accrued thereon and together with the Minimum Return and

the Prepayment/Maturity Amount shall be paid on the Maturity

Date.

     4.4  Notwithstanding the foregoing, the Holder may,

after acceleration of payment of the principal balance after

default, immediately commence all foreclosure activities and

process the same to sale without waiting for the submission of an

Appraisal from the Maker and without obtaining an Appraisal for

its own benefit, unless it so chooses.  In such event the Holder

shall obtain the Prepayment/Maturity Amount from the proceeds of

a foreclosure sale.

     4.5  Notwithstanding anything herein to the contrary,

Holder's Appraised Value shall in all events be used for purposes

of calculating the Residual Amount if the Residual Amount is

payable as a result of acceleration of maturity after default.

     4.6  In the event that the Capital Proceeds are such

that when determined in accordance with the provisions of the

Note, they are insufficient to fully pay the Minimum Return, all

sums in the Reserve Escrow Account and the Working Capital

Reserve Account shall be applied towards payment of the Minimum

Return.

                                 -22-




     5.  In addition to the foregoing, if the Maker shall fail

to make any payment of principal or Fixed Interest or the

Prepayment/Maturity Amount, including any Minimum Return,

Prepayment/Maturity Amount and all other payments due on the

Maturity Date, a late charge by way of damages shall be

immediately due and payable.  The Maker recognizes that any

default by the Maker in making the payments when due herein and

in the Mortgage securing payment hereof will result in the Holder

incurring additional expense in servicing the loan, in loss to

Holder of the use of the money due and in frustration to Holder

in meeting its loan commitments.  The maker agrees that, if for

any reason the Maker fails to pay the amounts due under the note

or under the Mortgage when due, the holder shall be entitled to

damages for the detriment caused thereby, but that it is

extremely difficult and impractical to ascertain the extent of

such damages.  The Maker therefore agrees that a sum equal to

five ($.05) cents for one each ($1.00) dollar of each payment

which becomes delinquent is a reasonable estimate of the said

damages to the Holder, which sum the Maker agrees to pay on

demand.

     6.  That upon default by the Maker and following the

acceleration of maturity as provided herein, a tender of payment

of the amount necessary to satisfy the entire indebtedness

evidenced hereby, made at any time prior to foreclosure sale

(including sale under any power of sale hereunder) by the Maker,

its successors assigns, or by anyone on behalf of the Maker,

its successors or assigns, shall be deemed to be a voluntary

                                 -23-




prepayment hereunder and such prepayment will therefore include

the Prepayment/Maturity Amount required under the payment terms

recited above.

     7.  Maker hereby further specifically acknowledges and

agrees that (a) the Prepayment/Maturity Amount is reasonable in

amount, (b) the Prepayment/Maturity Amount shall be paid without

prejudice to the right of Holder to collect any other amounts

provided to be paid hereunder or under the Mortgage or any other

document evidencing or securing the Loan evidenced hereby, and

(c) the Holder shall be entitled to bid all or a portion of the

Prepayment/Maturity Amount, at any foreclosure sale under the

Mortgage.  Maker hereby acknowledges and agrees that Holder would

not lend to Maker the Loan evidenced by the Note without Maker's

agreement to pay Holder the Prepayment/Maturity Amount, upon the

satisfaction of all or any portion of the principal indebtedness

evidenced hereby on a Prepayment Date or on the Maturity Date or

following the acceleration of the Maturity Date hereof by reason

of a default hereunder, including, without limitation, a default

arising from the conveyance of any right, title or interest in

the Mortgaged Premises encumbered by the Mortgage in violation of

the Mortgage.

     8.  All agreements between the Maker and the Holder hereof

are hereby expressly limited so that in no event shall the amount

paid or agreed to be paid to the Holder hereof as interest

(whether Fixed Interest, Prepayment/Maturity Amount or otherwise)

hereunder exceed the highest lawful rate now permissible under

applicable usury laws.  If the Holder of the Note would, but for

                                 -24-




the operation of this paragraph, ever receive as interest an

amount which would exceed the highest lawful rate which Holder

could lawfully receive as interest, such amount which would be

excessive interest shall be applied to the reduction of the

unpaid principal balance due hereunder and not to the payment of

interest; all payments made thereafter shall be appropriately

applied to interest and principal to give effect to the highest

lawful rate which Holder could lawfully receive as interest and

after such application, any excess shall be immediately refunded

to the Maker.  This provision shall control every other provision

of all agreements between the Maker and the Holder hereof.

     9.  If during the term of the Note the maximum rate of

interest, if any, now permitted by law for this transaction to be

lawfully charged should be increased, then for so long as such

increase is in effect, the applicable maximum rate permitted to

be charged as referred to in the paragraph immediately preceding

shall be deemed to be such increased rate.  If such maximum rate

of interest, if any, now permitted by law to be lawfully charged

for this transaction should be deleted so that there would be no

such maximum rate, then for purposes of this Loan, there shall

thereafter be no maximum rate limiting the amount that can be

charged.

     10.  Notwithstanding any provisions in the Note or in the

Mortgage securing the Note to the contrary, Holder hereof

covenants and agrees with Maker that in the event the Holder

shall, at any time, take action to enforce the collection of the

indebtedness evidenced by the Note and secured by the Mortgage or

                                 -25-




otherwise arising hereunder, it shall first proceed to foreclose

the Mortgage (including foreclosure pursuant to the exercise of

any power of sale in the Mortgage provided) instead of

instituting suit upon the Note and if, as a result of such

foreclosure and the sale of the property described herein, a

lesser sum is realized therefrom than the amount then due and

owing hereunder, the Holder hereof shall never institute any

action, suit, claim or demand in law or in equity against the

maker for or on account of such deficiency; provided, however,

that nothing in this paragraph contained will in any way affect

or impair the lien of the Mortgage securing the Note or any

liability for any intentional misrepresentation or intentionally

erroneous warranty of title made therein by Maker, all of which

will remain in full force and inure to the benefit of Holder

hereof and to any insurer of title of the real estate encumbered

by said Mortgage.  Neither the negative capital account of any

partner of Maker nor any obligation of any partner of Maker to

restore a negative capital account or to contribute capital to

Maker shall at any time be deemed to be an asset of Maker, and

Holder shall have any right to collect, enforce or proceed

against or with respect to any such negative capital account or

obligations; provided, however, that Holder and its successors

and assigns shall have the right to collect, enforce, or proceed

against or with respect to any such negative capital account or

partner's obligation to restore or contribute in order to recover

any sums due to Holder in connection with the misapplication of

rents under the Assignment.  Notwithstanding the foregoing, no

                                 -26-




General Partner of Carlyle Real Estate Limited Partnership-XI, or

any partner thereof, or any officer, director, shareholder,

principal, trustee or advisor of Carlyle Real Estate Limited

Partnership-XI or of any partner thereof or of Darvel Realty

Trust shall have any liability under this Note, the Mortgage, the

Assignment, the Escrow Agreement or any other of the Loan

Documents.

     11.  The name Darvel Realty Trust is the designation of the

trustees under a Declaration of Trust dated July 24, 1970, and

recorded with the Middlesex South District Registry of Deeds on

July 24, 1970 in Book 11865 at Page 580, as amended.  By

acceptance of the Note, Holder hereby agrees, notwithstanding

anything contained in the Note or the Mortgage or any other

document securing the Note to the contrary, in accordance with

such Declaration of Trust, to look solely to the property of

Darvel Realty Trust for the enforcement of any claims against

Darvel Realty Trust and that no trustee, officer, agent or

shareholder of Darvel Realty Trust shall be personally liable for

obligations of Darvel Realty Trust hereunder and the respective

properties of such individuals shall not be subject to claims of

Holder in respect of any liability to Holder of Darvel Realty

Trust hereunder.

     12.  The Maker and endorses hereof and all other who may

become liable for all or any part of the obligation of the Note

agree hereby to be jointly and severally bound and jointly and

severally waive and renounce any and all homestead and exemption

rights and the benefit of all valuation and appraisement

                                 -27-




privileges as against this debt or any renewal or extension

thereof, waive, demand, protest, notice of nonpayment and any and

all lack of diligence or delays in collection or enforcement

hereof waive the right to plead any and all statutes of

limitation as a defense to any demand on the Note or under the

Mortgage and expressly consent to any extension of time, release

of any party liable for this obligation, release of any of the

security of the Note, acceptance of other security therefor, or

any other indulgence or forbearance whatsoever.  Any such

extension, release, indulgence or forbearance may be made without

in any way affecting the personal liability of any party.

     13.  If default be made in the payment of any installment of

principal and/or Fixed Interest or any other sums when due under

the Note, which default shall continue for five (5) days without

notice, or if a default be made in the performance of any of the

other terms, covenants, conditions or warranties contained in the

Note or any of the terms, covenants, conditions or warranties

contained in the Mortgage or in the Assignment or in the Escrow

Agreement or in any other Loan Document which continues

uncorrected for fifteen (15) days, unless maker has commenced to

cure same within said fifteen (15) day period and thereafter

continues to diligently prosecute the cure thereof, then, at the

option of the Holder of the Note, the entire principal sum

evidenced hereby and secured by said Mortgage, together with

interest accrued thereon and all other sums then outstanding

under the Note, including without limitation unpaid Fixed

Interest and Prepayment/Maturity Amount, or the Mortgage, or

                                 -28-




the Assignment, without notice, shall immediately become due and

payable.  Failure to exercise this option shall not constitute a

waiver of the right to exercise the same in the event of any

subsequent default.

     14.  In the event the Maker fails to pay the entire unpaid

principal balance together with all accrued unpaid interest

including accrued Fixed Interest and the Prepayment/Maturity

Amount and other charges, if any, upon the Maturity Date, or upon

the earlier acceleration thereof, such outstanding principal

balance together with any accrued but unpaid interest including

Fixed Interest and the Prepayment/Maturity Amount and other

charges, if any, shall bear interest commencing on the date of

such default and continuing for so long as such default

continues, at the rate of twenty (20%) per cent per annum (the

"Default Rate"), but not to exceed the maximum legal rate

allowable, such interest to be compounded annually.

     15.  If any suit or action is instituted or an attorney is

employed to collect the Note or the Loan or any part thereof, the

Maker promises and agrees to pay all costs of collection

including reasonable attorney's fees.

     16.  During the existence of any default or deficiency under

the terms of the Note or under the terms of any instrument

executed or to be executed as security for the payment hereof,

the Holder is expressly authorized to apply all payments made on

the Note to the payment of such part of any delinquency as it may

elect.

                                 -29-




     17.  The remedies of the Holder hereof, as provided herein

or in the Mortgage or any other instrument securing the Note,

shall be cumulative and concurrent, and may be pursued

singularly, successively or together, at the sole discretion of

the Holder hereof, and may be exercised as often as occasion

therefor shall arise.  No act of omission or commission of the

Holder, including specifically any failure to exercise any right,

remedy or recourse, shall be deemed to be a waiver or release of

the same, such waiver or release to be effected only through a

written document executed by the Holder and then only to the

extent specifically recited therein.  A waiver or release with

reference to any one event shall not be construed as continuing,

as a bar to, or as a waiver or release of, any subsequent right,

remedy or recourse as to a subsequent event.

     18.  Maker understands that in making this Loan, Holder is

relying to a material extent upon the business expertise and net

worth of Maker and upon the continuing interest which Maker has

in the Mortgaged Premises.  Accordingly, in the event Maker

shall, directly or indirectly, voluntarily or involuntarily, (i)

sell, assign, transfer or dispose of all or any part of its

interest in the Mortgaged Premises, or (ii) further encumber, or

suffer to exist, any lien, other than the lien of the Mortgage

securing the Note against all or any part of, or any interest in

the Mortgaged Premises, or in the event the composition of the

Maker is changed (including without limitation, the transfer of

any beneficial interest in Maker or portion of such interest or

the change in control or composition of any beneficiary of Maker

                                 -30-




except for a transfer of less than five (5%) per cent over the

term of the loan of limited partnership interest among limited

partners of constituent partners of Maker or a transfer of a

limited partnership interest as a consequence of the death of a

limited partner) then, the Holder may at any time thereafter, at

its option, declare the unpaid principal of the Note and all

accrued Fixed Interest and the Prepayment/Maturity Amount thereon

immediately due and payable.  The transfer of an ownership

interest except as set forth above in the Maker shall be deemed a

sale of the Mortgaged Premises for the purposes of this

paragraph.  Notwithstanding the foregoing, Maker shall have the

right to sell, assign, transfer or dispose of the Mortgaged

Premises to a purchaser, assignee or transferee who (i) has a net

worth in excess $25,000,000.00 and (ii) in the reasonable

determination of Holder, has a favorable reputation and is

experienced in the operation, management and ownership of real

estate similar to the mortgaged Premises.

     Notwithstanding anything in this paragraph 18 to the

contrary, limited partnership interests in Carlyle Real Estate

Limited Partnership-XI ("Carlyle") which are presently owned by

an entity (which may include a corporation, partnership or

trust), that is neither JMB Realty Corporation ("JMB"), nor a JMB

Affiliate (as hereinafter defined), nor directly or indirectly

controlled or under common control with JMB or a JMB Affiliate,

may be sold, transferred or assigned without Holder's consent,

and, further, the partnership interest of Carlyle in the Maker

held directly or indirectly by JMB or by a JMB Affiliate may be

                                 -31-




sold, transferred or assigned without Holder's consent to any

existing general partner of Riverfront Office Park Associates,

the Massachusetts limited partnership which together with Carlyle

are the general partners of the Maker.  A "JMB Affiliate" means

(a) any entity (which may include a corporation, partnership or

trust) that is managed or directed on the basis of ownership of

economic interest and whose controlling ownership interests are

held by (i) JMB, (ii) persons or entities who are shareholders of

JMB ("JMB Shareholders") or (iii) a primary, secondary or

tertiary subsidiary of JMB or JMB Shareholders ("JMB

Subsidiary"); (B) any general or limited partnership having as

its managing general partner or partners (i) JMB, (ii) JMB

Shareholders, or (iii) JMB Subsidiary; (c) any real estate

investment trust, foundation, common fund or investor account for

which JMB, JMB Shareholders or JMB Subsidiary acts as the

investment manager or advisor; (d) any publicly-traded real

estate investment trust sponsored by, or in which of the time of

offering, more than ten (10%) per cent of the shares or units are

owned by, JMB, JMB Shareholders or JMB Subsidiary.

     19.  Whenever used, the singular number shall include the

plural, the plural the singular, the word "Mortgagor" shall mean

"Mortgagor and/or any subsequent owner or owners of the Mortgaged

Premises or any part thereof or interest therein," the word

"Mortgagee" shall mean "Mortgagee or any subsequent Holder of the

Mortgage," and the words "Maker" and "Holder" shall include their

respective successors and assigns.  The Note is to be construed

according to the laws of the Commonwealth of Massachusetts.

                                 -32-




     20.  The Maker hereby irrevocably and unconditionally (a)

submits to personal jurisdiction in the Commonwealth of

Massachusetts over any suit, action or proceeding arising out of

or relating to the Loan Documents, and (b) waives any and all

personal rights under the laws of any state (i) to the right, if

any, to trial by jury, (ii) to object to jurisdiction within the

Commonwealth of Massachusetts or venue in any particular forum

within the Commonwealth of Massachusetts, and (iii) to the right,

if any, to claim or recover any special, exemplary, punitive or

consequential damages or any damages other than actual damages.

The Maker agrees that, in addition to any methods of service of

process provided for under applicable law, all services or process

in any such suit, action or proceeding may be made by certified

or registered mail, return receipt requested, directed to the

Maker at the address set forth above, and service so made shall

be complete five (5) days after the same shall be so mailed.

Nothing contained herein, however, shall prevent the Holder from

bringing any suit, action or proceeding or exercising any rights

against any security and against Maker, and against any property

of Maker, in any other state.  Initiating such suit, action or

proceeding or taking such action in any state shall in no event

constitute a waiver of the agreement contained herein that the

laws of the Commonwealth of Massachusetts shall govern the rights

and obligations of the Maker and the Holder hereunder or the

submission herein made by the Maker to personal jurisdiction

within the Commonwealth of Massachusetts.

                                 -33-




     EXECUTED as a sealed instrument as of the day and year first

above written.

WITNESS:                      RIVERFRONT OFFICE PARK JOINT
                              VENTURE, a Massachusetts general
                              partnership

                              By:  RIVERFRONT OFFICE PARK
                                   ASSOCIATES, a Massachusetts
                                   limited partnership and a
                                   general partner of Riverfront
                                   Office Park Joint Venture

                                   By:  Darvel Realty Trust, a
                                        Massachusetts Business
                                        Trust and General Partner
                                        Of Riverfront Office Park
                                        Associates



                                        By:
                                             Michael P. Sullivan,
                                             Vice President and a
                                             Trustee of Darvel Realty
                                             Trust

                                        By:  Macomber-Riverfront
                                             Associates, a
                                             Massachusetts limited
                                             partnership and General
                                             Partner of Riverfront
                                             Office Park Associates



                                        By
                                        Byron Gilchrest,
                                        Managing General Partner

                                        By:  Cod-Riverfront
                                             Associates, a
                                             Massachusetts partnership
                                             and General Partner of
                                             Riverfront Office Park
                                             Associates



                                        By
                                        Lawrence A. Bianchi,
                                        General Partner

                                             and

                                 -34-




                              By:  CARLYLE REAL ESTATE LIMITED
                                   PARTNERSHIP-XI, an Illinois
                                   limited partnership and a
                                   general partner of Riverfront
                                   Office Park Joint Venture

                                   By:  JMB Realty Corporation, a
                                        Delaware Corporation,
                                        Corporate General Partner
                                        of Carlyle Real Estate
                                        Limited Partnership-XI



                                        By
                                        Vice President






















































                                 -35-