Exhibit 10.12
                                       
                                     COPY
                              DEED OF TRUST NOTE


$11,800,000.00                                          Baltimore, Maryland
                                                        September 20, 1988


FOR VALUE RECEIVED, BROWN'S WHARF LIMITED PARTNERSHIP, a Maryland limited 
partnership (the "Borrower"), promises to pay to the order of MERCANTILE-SAFE 
DEPOSIT AND TRUST COMPANY, a Maryland banking corporation (the "Bank"), at 
its principal office in Baltimore, Maryland, or at such other place or to 
such other party as the holder hereof may from time to time designate, the 
principal sum of ELEVEN MILLION EIGHT HUNDRED THOUSAND DOLLARS 
($11,800,000.00) or so much thereof as may be advanced by Bank to Borrower 
pursuant to the terms of a Building Loan Agreement of even date herewith (the 
"Building Loan Agreement") with interest on the unpaid principal balance from 
the date of this Deed of Trust Note, until paid, at either of the interest 
rates as follows:

          (1)  A rate of one quarter of one percent (.25%) per annum in 
          excess of the Prime Rate. "Prime Rate" means the prime commercial 
          lending rate of the Bank as publicly announced to be in effect from 
          time to time. The Prime Rate is not necessarily the lowest rate of 
          interest charged by the Bank for commercial or other types of 
          loans. It is understood that the Prime Rate is only one of the 
          bases for computing interest on loans made by the Bank and that by 
          basing interest on the Prime Rate, the Bank has not committed to 
          charge and the Borrower has not in any way bargained for interest 
          based on a lower or the lowest rate at which the Bank may now or 
          in the future make loans to other borrowers. Any change in the rate 
          of interest as a result of a change in the Prime Rate shall be 
          effective as of the date of the change in the Prime Rate; or,

          (2)  On the condition that Bank be given five (5) business days 
          notice of Borrower's choice, Borrower may fix the rate of interest 
          for each advance, under the Building Loan Agreement, after ninety 
          (90) days from the date on which said Advance was made for a period 
          of three (3) months, six (6) months or one (1) year. The rate of 
          interest for the three (3) month period shall be one and three 
          quarters percent (1.75%) in excess of the three (3) month "CD Rate" 
          (as hereinafter defined); the rate of interest for the six (6) 
          month period shall be one and three quarters percent (1.75%) in 
          excess of the six (6) month CD



          Rate; the rate of interest for the one (1) year period shall be one 
          and three quarters percent (1.75%) in excess of the one (1) year 
          CD Rate. "CD Rate" means the rate for Certificates of Deposit 
          appearing in the Wall Street Journal, Eastern Edition, plus a CD 
          Reserve Requirement (as hereinafter defined), and shall be average 
          negotiable rates paid by major New York banks on primary new issues 
          of negotiable Certificates of Deposit usually on amounts of 
          $1,000,000.00 and more; the minimum unit is $100,000.00. "CD 
          Reserve Requirement" shall, on any day mean that percentage 
          (expressed as a decimal fraction) which is in effect on such day, 
          as provided by the Board of Governors of the Federal Reserve System 
          (or any successor governmental body) for determining the maximum 
          reserve requirements (including without limitation, basic, 
          supplemental, marginal and emergency reserves) under Regulation D 
          applicable to 3-month non-personal time deposits in units of 
          $100,000.00 or more (issued by member banks of the Federal Reserve 
          Bank of New York having time deposits exceeding $1,000,000,000.00) 
          rounded to the next highest .01 of one percent. Each determination 
          by Lender of the CD Reserve Requirement shall, in the absence of 
          manifest error, be conclusive and binding.

          In all instances in which the CD Rate does not apply (including 
instances where no CD Rate election notice is given), the rate of interest to 
be paid hereunder shall be that set forth in the paragraph numbered 1 above.

          Except when the loan evidenced hereby shall bear interest at a CD 
Rate, the interest rate in effect from time to time shall be reduced to the 
Prime Rate when all of the following shall occur:

          (1) when (a) Bank has approved the form lease for the "Project," 
defined in the Building Loan Agreement, which approval shall not be 
unreasonably withheld, and (b) Bank has approved the creditworthiness of each 
tenant. Leases submitted to the Bank for approval shall be deemed to be 
approved unless Bank notifies Borrower to the contrary within fifteen (15) 
days of submittal; and

          (2) when leases (approved as provided above) have been executed 
which provide for (i) rents of at least Fifteen Dollars ($15.00) absolutely 
net or Eighteen Dollars ($18.00) gross per square foot for at least 70% 
(73,430 square feet) of the Project, and (ii) terms of at least five (5) 
years for at least 80% (83,920 square feet) of the Project; and

                                       
                               Page 2 of 6 Pages





         (3)  when the leases have been executed by the tenant and 
collaterally assigned to Bank; and

         (4)  when the tenants have executed and delivered estoppel letters 
and subordination, non-disturbance and attornment agreements.

         Payments of accrued interest only shall be due and payable in 
consecutive monthly installments commencing October 1, 1988, and continuing on 
the first day of each month thereafter until September 20, 1995, at which 
time the entire unpaid balance of principal and any accrued but unpaid 
interest, if not sooner paid, shall be due and payable in full.

         All payments hereunder shall be applied first to the payment of 
interest and any balance, if any, to the payment of principal. Interest shall 
be charged, calculated on the basis of a 360 day year factor applied to 
actual days.  Interest and principal shall be payable in lawful money of the 
United States, which shall be legal tender in payment of all debts and dues, 
public and private at the time of payment.

         "Loan Year" means any twelve (12) consecutive month period 
commencing October 1, 1988 and on each yearly anniversary thereof.

         Upon the occurrence of an "Event of Default" (as defined 
hereinafter), the entire unpaid principal balance shall bear interest 
thereafter at the rate of one percent (1%) per annum in excess of the then 
applicable interest rate due hereunder until such "Event of Default" is cured.

         The principal sum may be prepaid in whole or in part at any time 
after ten (10) days prior written notice, without payment of premium or 
penalty therefor.

         Borrower shall pay to Bank a loan origination Fee in the amount of 
one percent (1%) of the Loan, or One Hundred Eighteen Thousand Dollars 
($118,000.00), which shall be paid as follows: Fifty Nine Thousand Dollars 
($59,000.00) shall be paid upon the execution of this Deed of Trust Note, and 
Fifty Nine Thousand Dollars ($59,000.00) shall be paid on the earlier to 
occur of the commencement of the third (3rd) Loan Year, or the payment, in 
full, of this Deed of Trust Note.

         This Deed of Trust Note is secured by a Deed of Trust and Security 
Agreement of even date herewith from the Borrower to Herbert B. Williams and 
Bruce D. McLean, Trustees, and recorded among the Land Records of Baltimore 
City, Maryland (the "Deed of Trust").


                                Page 3 of 6 Pages




         All notices, requests and demands upon the respective parties hereto 
shall be in writing and shall be sent by hand delivery or Federal Express or 
other commercial courier addressed as follows or to such other address as the 
respective party may designate by a notice to the others:

         if to the Bank

              Mercantile-Safe Deposit & Trust Company
              Two Hopkins Plaza
              Baltimore, Maryland 21201
              Attention: Herbert B. Williams
                         Senior Vice President

         if to the Borrower

              Brown's Wharf Limited Partnershipj
              c/o CPI Brown's Wharf, Inc.
              250 West Pratt Street
              Baltimore, Maryland 21201-2423
              Attention: Secretary, 23rd Floor

         With copies to

              Constellation Holdings, Inc.
              250 West Pratt Street
              Baltimore, Maryland 21201-2423
              Attention: General Counsel, 23rd Floor

              and

              Historical Developers of Pennsylvania, Inc.
              201 North Broad Street
              Philadelphia, Pennsylvania 19107
              Attention: President

All such notices shall be deemed to have been given one (1) business day 
after the date on which the same was sent or upon receipt, whichever shall 
first occur.

         The happening of any one or more of the following events shall 
constitute an Event of Default under this Note:

              (a)  The Borrower fails to make any payment within five (5) 
days of the date when due; or

              (b)  The Borrower fails to perform or comply with any other 
covenant, term or condition of this Agreement, and such failure continues 
uncured for 30 days after written notice thereof from the Bank to the 
Borrower; or 


                                Page 4 of 6 Pages





          (c) An Event of Default (as defined therein) shall have occurred 
and be continuing under the Deed of Trust. Guaranty, or Building Loan 
Agreement; or

          (d) Any representation or warranty made by the Borrower in this 
Note proves to have been incorrect or misleading in any material respect 
either on the date when made or on the date reaffirmed pursuant to the terms 
of this Note.

     It is expressly agreed that upon the happening of an Event of Default 
hereunder or under any of the Loan Documents, the entire unpaid balance of 
the principal sum due hereunder, plus all accrued interest shall, at the 
option of the holder hereof, at once become and be due and payable.

     Upon the occurrence of an Event of Default hereunder and if this Note is 
collected by an attorney, the Borrower agrees to pay all costs of collection, 
including reasonable and verifiable attorney's fees.

     The maker and endorsers hereof jointly and severally, and all others who 
may become liable for all or any part of this obligation severally, waive 
demand, notice of presentment for payment, notice of protest and notice of 
the dishonor and non-payment.

     Borrower stipulates and warrants that the purpose of the loan evidenced 
hereby is for the purpose of a business or commercial investment within the 
meaning of Sections 12-101(c) and 12-103(e) of the Commercial Law Article of 
the Annotated Code of Maryland. Borrower further stipulates that all loan 
proceeds will be used for said purposes.

     Borrower also covenants and agrees that in the event that any sum 
required hereunder or under said Deed of Trust should not be received by the 
holder hereof within ten (10) days from its due date, a late charge of five 
cents ($.05) for each One Dollar ($1.00) so overdue may, in addition to any 
other remedies provided for hereunder, be charged for the purpose of 
defraying expenses incident to handling such delinquent payments.

     In the event that any provision (or any part of any provision) 
contained in this Note shall for any reason be held to be invalid, illegal 
or unenforceable in any respect, such invalidity, illegality or 
unenforceability shall not affect any other provision (or remaining part of 
the affected provision) of this Note, but this Note shall be construed as if 
such invalid, illegal or unenforceable provision (or part thereof) had never 
been contained herein but only to the extent it is invalid, illegal or 
unenforceable. All words beginning with a capital letter and not defined 
herein shall have the meaning provided in the Deed of Trust.

     Borrower covenants and agrees that this Deed of Trust Note shall be 
governed by and construed in accordance with the laws of the State of 
Maryland.

WITNESS:                          BROWN'S WHARF LIMITED PARTNERSHIP
                                  By:  CPI Brown's Wharf, Inc.,
                                       a general partner

/s/                               By: /s/  
- --------------------------                 ------------------------------------
                                           
                                            Treasurer/Assistant Secretary


                                  By:  HISTORICAL DEVELOPERS OF
                                       PENNSYLVANIA, INC., doing
Attest:                                business in Maryland as
                                       Historical Real Estate
                                       Developers, Inc.,
                                       a general partner

/s/                               By: /s/  
- --------------------------                 ------------------------------------

Assistant Secretary                        Vice President