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                                                                  Exhibit 10.21

                                PROMISSORY NOTE

                                 DEFINED TERMS

EXECUTION DATE:  As of November 25, 1998

CITY AND STATE OF SIGNING:  Arlington, Virginia

LOAN AMOUNT:  $21,500,000.00

INTEREST RATE:  6.8% per annum

BORROWER:  Arlington Square Limited Partnership, a Virginia limited Partnership

BORROWER'S ADDRESS:        c/o The Washington Corporation
                           4650 East-West Highway, Suite 251
                           Bethesda, MD 20814
                           Attention: William N. Demas

HOLDER:  Metropolitan Life Insurance Company, a New York corporation

HOLDER'S ADDRESS:          Metropolitan Life Insurance Company
                           200 Park Avenue, 12th Floor
                           New York, New York 10166
                           Attention: Senior Vice-President
                                       Real Estate Investments

                  and:     Metropolitan Life Insurance Company
                           One Madison Avenue
                           New York, New York 10010-3690
                           Attention: Vice-President and Investment Counsel
                                       Real Estate Investments

MATURITY DATE:  December 1, 2010


INTEREST ONLY PERIOD:  The period
from the Advance Date and ending
on the last day of the month in
which the Advance Date occurs.

MONTHLY INSTALLMENT:  Equal monthly
installments of principal and
interest at the Interest Rate each
in the amount of $147,057.86.

The Monthly Installment is based
upon an amortization period of 26
years.


ADVANCE DATE:  The date funds are disbursed
Borrower.

PRINCIPAL AND INTEREST INSTALLMENT DATE:
The first day of the second calendar month
following the Advance Date.


PERMITTED PREPAYMENT PERIOD:  During the 90
day period prior to the Maturity Date,
Borrower may prepay the Loan without a
Prepayment Fee on 30 days' prior written
notice to Holder.  In addition, commencing on
the first day of the 72nd month following the
month in which the Advance Date occurs,
Borrower may prepay the Loan with a
Prepayment Fee on 60 days' prior written
notice to Holder.


LIABLE PARTIES:  The Washington Corporation

ADDRESSES OF LIABLE PARTIES:  4650 East-West Highway, Suite 251
                              Bethesda, MD 20814



LATE CHARGE:  An amount equal to four cents ($.04) for each dollar that is
overdue.

DEFAULT RATE:  The lesser of (i) an annual rate equal to the Interest Rate plus
four percent (40%), and (ii) the highest rate permitted under applicable law.

NOTE:  This Promissory Note, together with all extensions, renewals,
amendments, modifications and restatements hereof.

DEED OF TRUST:  Deed of Trust, Security Agreement and Fixture Filing dated as
of the Execution Date granted by Borrower to secure repayment of the Note
together with all extensions, renewals, modifications, amendments and
restatements thereof.

LOAN DOCUMENTS:  This Note, the Deed of Trust and any other documents related
to this Note and/or the Deed of Trust and all renewals, amendments,
modifications, restatements and extensions of these documents.

GUARANTY:  Guaranty Agreement dated as of the Execution Date and executed by
Liable Parties in favor of Holder, together with all renewals, amendments,
modifications and restatements thereof.

UNSECURED INDEMNITY AGREEMENT:  Unsecured Indemnity Agreement dated as of the
Execution Date and executed by Borrower and Liable Parties in favor of Holder,
together with all renewals, amendments, modifications and restatements thereof.
The Unsecured Indemnity Agreement and Guaranty are not Loan Documents and shall
survive repayment of the Loan or other termination of the Loan Documents.

PROPERTY:  The property defined as such in the Deed of Trust.

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          FOR VALUE RECEIVED, Borrower promises to pay to the order of Holder
at Holder's Address or such other place as Holder may from time to time
designate, the Loan Amount with interest payable in the manner described below,
in money of the United States of America that at the time of payment shall be
legal tender for payment of all obligations.

          Capitalized terms which are not defined in this Note shall have the
meanings set forth in the Deed of Trust.

          1.  PAYMENT OF PRINCIPAL AND INTEREST.  Principal and interest under
this Note shall be payable as follows:

                  (a) Interest on the funded portion of the Loan Amount shall
accrue from the Advance Date at the Interest Rate and shall be paid on the
first day of the first calendar month following the Advance Date;

                  (b) Commencing on the Principal and Interest Installment Date
and continuing on the first day of each calendar month thereafter, to and
including the first day of the calendar month immediately preceding the
Maturity Date, Borrower shall pay the Monthly Installment; and

                  (c) On the Maturity Date, a final payment in the aggregate
amount of the unpaid principal sum evidenced by this Note, all accrued and
unpaid interest, and all other sums evidenced by this Note or secured by the
Deed of Trust and/or any other Loan Documents as well as any additional
advances under the Deed of Trust that may be made to or on behalf of Borrower
by Holder following the Advance Date (collectively, the "AGGREGATE
INDEBTEDNESS"), shall become immediately payable in full.

       Borrower acknowledges and agrees that a substantial portion of the
original Loan Amount shall be outstanding and due on the Maturity Date.

       Interest shall be calculated on the basis of a thirty (30) day month and
a three hundred sixty (360) day year, except that (i) if the Advance Date
occurs on a date other than the first day of a calendar month, interest payable
for the period commencing on the Advance Date and ending on the last day of the
month in which the Advance Date occurs shall be calculated on the basis of the
actual number of days elapsed over a 365 day or 366 day year, as applicable,
and (ii) if the Maturity Date occurs on a date other than the last day of the
month, interest payable for the period commencing on the first day of the month
in which the Maturity Date occurs and ending on the Maturity Date shall be
calculated on the basis of the actual number of days elapsed over a 365 day or
366 day year, as applicable.

         2.  APPLICATION OF PAYMENTS.  At the election of Holder, and to the
extent permitted by law, all payments shall be applied in the order selected by
Holder to any expenses, prepayment fees, late charges, escrow deposits and
other sums due and payable under the Loan Documents, and to unpaid interest at
the Interest Rate or at the Default Rate, as applicable.  The balance of any
payments shall be applied to reduce the then unpaid Loan Amount.

         3.  SECURITY.  The covenants of the Deed of Trust are incorporated by
reference into this Note.  This Note shall evidence, and the Deed of Trust
shall secure the Aggregate Indebtedness.

         4.  LATE CHARGE.  If any payment of interest, any payment of a Monthly
Installment or any payment of a required escrow deposit is not paid within 7
days of the due date, Holder shall have the option to charge Borrower the Late
Charge.  The Late Charge is for the purpose of defraying the expenses incurred
in connection with handling and processing delinquent payments and is payable
in addition to any other remedy Holder may have.  Unpaid Late Charges shall
become part of the Aggregate Indebtedness and shall be added to any subsequent
payments due under the Loan Documents.

         5.  ACCELERATION UPON DEFAULT.  At the option of Holder, if Borrower
fails to pay any sum specified in this Note when due after giving effect to any
grace periods, or if an Event of Default occurs, the Aggregate Indebtedness,
and all other sums evidenced and/or secured by the Loan Documents, including
without limitation any applicable prepayment fees (collectively, the
"ACCELERATED LOAN AMOUNT") shall become immediately due and payable.

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         6.  INTEREST UPON DEFAULT.  The Accelerated Loan Amount shall bear
interest at the Default Rate which shall never exceed the maximum rate of
interest permitted to be contracted for under the laws of the Commonwealth of
Virginia.  The Default Rate shall commence upon the occurrence of an Event of
Default and shall continue until all then-existing Events(s) of Default shall
have been cured.

         7.  LIMITATION ON INTEREST.  The agreements made by Borrower with
respect to this Note and the other Loan Documents are expressly limited so that
in no event shall the amount of interest received, charged or contracted for by
Holder exceed the highest lawful amount of interest permissible under the laws
applicable to the Loan.  If at any time performance of any provision of this
Note or the other Loan Documents results in the highest lawful rate of interest
permissible under applicable laws being exceeded, then the amount of interest
received, charged or contracted for by Holder shall automatically and without
further action by any party be deemed to have been reduced to the highest
lawful amount of interest then permissible under applicable laws.  If Holder
shall ever receive, charge or contract for, as interest, an amount which is
unlawful, at Holder's election, the amount of unlawful interest shall be
refunded to Borrower (if actually paid) or applied to reduce the then unpaid
Loan Amount.  To the fullest extent permitted by applicable laws, any amounts
contracted for, charged or received under the Loan Documents included for the
purpose of determining whether the Interest Rate would exceed the highest
lawful rate shall be calculated by allocating and spreading such interest to
and over the full stated term of this Note.

         8.  PREPAYMENT.   Borrower shall not have the right to prepay all or
any portion of the Loan Amount at any time during the term of this Note except
as expressly set forth in the Defined Terms.  If Borrower provides notice of
its intention to prepay, the Accelerated Loan Amount shall become due and
payable in accordance with the Defined Terms.

         9.  PREPAYMENT FEE.

                  (a) Any tender of payment by Borrower or any other person or
entity of the Aggregate Indebtedness, other than as expressly provided in the
Loan Documents, shall constitute a prohibited prepayment. If a prepayment of all
or any part of the Aggregate Indebtedness is made following (i) an Event of
Default and an acceleration of the Maturity Date, (ii) the application of money
to the principal of the Loan after a casualty or condemnation, or (iii) in
connection with a purchase of the Property or a repayment of the Aggregate
Indebtedness at any time before, during or after, a judicial or non-judicial
foreclosure or sale of the Property, then to compensate Holder for the loss of
the investment, Borrower shall pay an amount equal to the Prepayment Fee (as
hereinafter defined).

                  (b) The "PREPAYMENT FEE" shall be the greater of (A) the
Prepayment Ratio (as hereinafter defined) multiplied by the difference between
(x) and (y), where (x) is the present value of all remaining payments of
principal and interest including the outstanding principal due on the Maturity
Date, discounted at the rate which, when compounded monthly, is equivalent to
the Treasury Rate compounded semi-annually, and (y) is the amount of the
principal then outstanding, or (B) one percent (1%) of the amount of the
principal being prepaid.

                  (c) THE "TREASURY RATE" shall be the annualized yield on
securities issued by the United States Treasury having a maturity equal to the
remaining stated term of the Note, as quoted in the FEDERAL RESERVE STATISTICAL
RELEASE [H.15 (519)] under the heading "U.S. Government Securities--Treasury
Constant Maturities" for the date on which prepayment is being made.  If this
rate is not available as of the date of prepayment, the Treasury Rate shall be
determined by interpolating between the yield on securities of the next longer
and next shorter maturity.  If the Treasury Rate is no longer published, Holder
shall select a comparable rate.  Holder will, upon written request, provide an
estimate of the amount of the Prepayment Fee two weeks before the date of the
scheduled prepayment.

                  (d) The "PREPAYMENT RATIO" shall be a fraction, the numerator
of which shall be the amount of principal being prepaid, and the denominator of
which shall be the principal then outstanding.

                  (e) Notwithstanding the foregoing provisions of this SECTION
9, no Prepayment Fee shall be due in connection with a prepayment of all or a
portion of the Aggregate Indebtedness occasioned by the exercise by a tenant of
the Property which is a governmental instrumentality of its right at law (and
without implying any consent by Holder

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to any such contractual right to be contained in an express provision of any
present or future lease of the Property) to condemn the Property of any
interest therein in connection with or in lieu of a holdover occupancy by such
tenant.

                   10.  WAIVER OF RIGHT TO PREPAY NOTE WITHOUT PREPAYMENT FEE.
Borrower acknowledges that Holder has relied upon the anticipated investment
return under this Note in entering into transactions with, and in making
commitments to, third parties and that the tender of any prohibited prepayment,
shall, to the extent permitted by law, include the Prepayment Fee.  Borrower
agrees that the Prepayment Fee represents the reasonable estimate of Holder and
Borrower of a fair average compensation for the loss that may be sustained by
Holder as a result of a prohibited prepayment of the Note and it shall be paid
without prejudice to the right of Holder to collect any other amounts provided
to be paid under the Loan Documents.

                   BORROWER EXPRESSLY (A) WAIVES ANY RIGHTS IT MAY HAVE UNDER
APPLICABLE STATE LAW TO PREPAY THIS NOTE, IN WHOLE OR IN PART, WITHOUT FEE OR
PENALTY, UPON ACCELERATION OF THE MATURITY DATE OF THE NOTE, AND (B) AGREES
THAT IF, FOR ANY REASON, A PREPAYMENT OF THIS NOTE IS MADE, UPON OR FOLLOWING
ANY ACCELERATION OF THE MATURITY DATE OF THIS NOTE BY HOLDER ON ACCOUNT OF ANY
DEFAULT BY BORROWER UNDER ANY LOAN DOCUMENT, INCLUDING BUT NOT LIMITED TO ANY
TRANSFER, FURTHER ENCUMBRANCE OR DISPOSITION WHICH IS PROHIBITED OR RESTRICTED
BY THE DEED OF TRUST, THEN BORROWER SHALL BE OBLIGATED TO PAY CONCURRENTLY THE
PREPAYMENT FEE SPECIFIED IN SECTION 9.  BY EXECUTING THIS NOTE, BORROWER AGREES
THAT HOLDER'S AGREEMENT TO MAKE THE LOAN AT THE INTEREST RATE AND FOR THE TERM
SET FORTH IN THIS NOTE CONSTITUTES ADEQUATE CONSIDERATION FOR THIS WAIVER AND
AGREEMENT.

         11.  LIABILITY OF BORROWER.  Upon the occurrence of an Event of
Default, except as provided in this SECTION 11, Holder will look solely to the
Property and the security under the Loan Documents for the repayment of the
Loan and will not enforce a deficiency judgment against Borrower.  However,
nothing contained in this Section 11 shall limit the rights of Holder to
proceed against Borrower and the general partner of Borrower and/or the
Liable Parties, (i) to enforce any leases entered into by Borrower or its
affiliates as tenant, guarantees, or other agreements entered into by
Borrower in a capacity other than as borrower or any policies of insurance;
(ii) to recover damages for fraud, material misrepresentation, breach of
warranty or waste; (iii) to recover any condemnation proceeds or insurance
proceeds or other similar funds which have bow misapplied by Borrower or
which, under the terms of the Loan Documents, should have been paid to
Holder; (iv) to recover any tenant security deposits, tenant letters of
credit or other deposits or fees paid to Borrower that are part of the
collateral for the Loan or prepaid rents for a period of more than 30 days
which have not been delivered to Holder; (v) to recover Rents and Profits (as
defined in the Deed of Trust) received by Borrower after the first day of the
month in which an Event of Default and prior to the date Holder acquires
title to the Property which have not been applied to the Loan or in
accordance with the Loan Documents to operating and maintenance expenses of
the Property; (vi) to recover damages, costs and expenses arising from, or in
connection with the provisions of the Deed of Trust pertaining to hazardous
materials or the Unsecured Indemnity Agreement; (vii) to recover all amounts
due and payable pursuant to Sections 11.06 and 11.07 of the Deed of Trust;
and/or (viii) to recover damages arising from Borrower's failure to comply
with the provisions of the Deed of Trust pertaining to ERISA.

      The limitation of liability set forth in this Section 11 shall not apply
and the Loan shall be fully recourse in the event that Borrower commences a
voluntary bankruptcy or insolvency proceeding or an involuntary bankruptcy or
insolvency proceeding is commenced against Borrower and is not dismissed within
ninety (90) days of filing.  In addition, this Note shall not waive any rights
which Holder would have under any provisions of the Bankruptcy Code to file a
claim for the full amount of the Aggregate Indebtedness or to require that the
Property shall continue to secure all of the Aggregate Indebtedness.

         12.  WAIVER BY BORROWER.  Borrower and others who may become liable
for the payment of all or any part of this Note and each of them, waive
diligence, demand, presentment for payment, notice of nonpayment, protest,
notice of dishonor and notice of protest, notice of intent to accelerate and
notice of acceleration and specifically consent to and waive notice of any
amendments, modifications, renewals or extensions of this Note, including the
granting of extension of time for payment, whether made to or in favor of
Borrower or any other person or persons.

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         13.  EXERCISE OF RIGHTS.  No single or partial exercise by Holder, or
delay or omission in the exercise by Holder, of any right or remedy under the
Loan Documents shall waive or limit the exercise of any such right or remedy.
Holder shall at all times have the right to proceed against any portion of or
interest in the Property in the manner that Holder may deem appropriate,
without waiving any other rights or remedies.  The release of any party under
this Note shall not operate to release any other party which is liable under
this Note and/or under the other Loan Documents or under the Guaranty or the
Unsecured Indemnity Agreement.

         14.  FEES AND EXPENSES.  If Borrower defaults under this Note,
Borrower shall be personally liable for and shall pay to Holder, in addition
to the sums stated above, the costs and expenses of enforcement and
collection, including, without limitation, a reasonable sum as an attorney's
fee.  This obligation is not limited by SECTION 11.

         15.  NO AMENDMENTS.  This Note may not be modified or amended except
in a writing executed by Borrower and Holder.  No waivers shall be effective
unless they are set forth in a writing signed by the party which is waiving a
right.  This Note and the other Loan Documents are the final expression of the
lending relationship between Borrower and Holder.

         16.  GOVERNING LAW.  This Note shall in all respects be governed by,
and construed and enforced in accordance with, the laws of the Commonwealth of
Virginia, without regard to conflict of laws principles.

         17.  CONSTRUCTION.  The words "Borrower and "Holder" shall be deemed
to include their respective heirs, representatives, successors and assigns, and
shall denote the singular and/or plural, and the masculine and/or feminine, and
natural and/or artificial persons as appropriate.  The provisions of this Note
shall remain in full force and effect notwithstanding any changes in the
shareholders, partners or members of Borrower.  If more than one party is
Borrower, the obligations of each party shall be joint and several.  The
captions in this Note are inserted only for convenience of reference and do not
expand, limit or define the scope or intent of any section of this Note.

         18.  NOTICES.  All notices, demands, requests and consents permitted
or required under this Note shall be given in the manner prescribed in this
Deed of Trust.

         19.  TIME OF THE ESSENCE.  Time shall be of the essence with respect
to all of Borrower's obligations under this Note.

         20.  SEVERABILITY.  If any provision of this Note should be held
unenforceable or void, then that provision shall be deemed separable from the
remaining provisions and shall not affect the validity of this Note, except that
if that provision relates to the payment of interest or principal provided for
herein, then Holder may, at its option, declare the Aggregate Indebtedness
(together with the Prepayment Fee) immediately due and payable.

                   [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

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                  IN WITNESS WHEREOF, Borrower has, by its duly authorized
representatives, executed this Note as of the Execution Date.

                                    ARLINGTON SQUARE LIMITED PARTNERSHIP, a
                                    Virginia limited partnership

                                    By: Arlington Square, Inc., a Virginia
                                        corporation, general partner



                                        By: /s/ William N. Demas [SEAL]
                                            ---------------------------
                                            William N. Demas
                                            President

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                                IDENTIFICATION


         This is to certify that this is the Promissory Note described in that
certain Deed of Trust, Security Agreement and Fixture Filing, dated as of even
date therewith, from the Maker of the Promissory Note to Keith J. Willner, and
Scott A. Morehouse, Trustees, conveying certain property (described in said
Deed of Trust, Security Agreement and Fixture Filing) situated in the
Commonwealth of Virginia, said Deed of Trust, Security Agreement and Fixture
Filing having been executed in my presence.

                                 /s/ VERONICA JENKINS
                                 --------------------
                                 Notary Public

My Commission Expires:


-----------------------
[Notarial Seal]


                        VERONICA JENKINS
             NOTARY PUBLIC, DISTRICT OF COLUMBIA
             MY COMMISSION EXPIRES April 30, 2003




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