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                                                                     EXHIBIT 4.8


                                 PROMISSORY NOTE

$50,000.00                                                   Date: July 10, 1999


FOR VALUE RECEIVED, CHICAGO MAP CORPORATION, an Illinois corporation
("Borrower"), promises to pay to JOHN B. MCLEAN, an individual ("Lender"), or
order, the principal amount of FIFTY THOUSAND DOLLARS ($50,000,00) with interest
on the unpaid principal balance at one percent (1%) per month (the "Loan").

This Promissory Note is the Note referred to as Exhibit A to the Interim Loan
Agreement of even date herewith entered into by Borrower and Lender. Pursuant to
the terms of the Interim Loan Agreement, Lender has made the Loan to Borrower as
follows:

1.   Payment and Term. The Loan shall bear interest on the principal balance at
     1% per month from and after the date thereof until payment in full. The
     principal and interest, is due and payable as follows:

(a)  The Note is due in full four (4) months from the date hereof, unless
     extended by Lender pursuant to written notice thereof, or such other
     agreement as may be entered into between Lender and Borrower with respect
     thereto; and

(b)  Borrower may, but is not obligated to, make periodic payments in part or
     full payment of the Loan until due.

2.   Application of Payments. Unless applicable law provides otherwise, all
     payments received by Lender shall be applied by Lender first in payment of
     interest payable and next to the principal.

3.1  Events of Default. Upon the occurrence and during the continuance of any
     one or more events hereinafter enumerated, Lender may forthwith or at any
     time thereafter during the continuance of any such event, by notice in
     writing to Borrower, declare the unpaid balance of the principal and
     interest shall become and shall be immediately due and payable without
     presentation, demand, protest, notice of protest, or other notice of
     dishonor, all of which are hereby expressly waived by Borrower, such events
     being as follows:

(a)  Default in the payment of the principal and interest of the Note or any
     portion thereof when the same shall become due and payable, whether at
     maturity as therein expressed, by acceleration, or otherwise, unless cured
     within 10 days after notice thereof by the holder of such Note to Borrower;




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(b)  The creditors under any priority secured indebtedness of Borrower shall
     declare the amounts due thereunder to be due and payable following default;

(c)  Default in the due observance or performance of any other covenant or
     obligation contained in the Interim Loan Agreement, this Note or the
     Acquisition Agreement unless observed or performed within 10 days after
     notice thereof to Borrower by lender; provided, if compliance is not
     possible within 10 days, default shall occur upon failure within 10 days to
     take steps that will produce compliance as soon as is reasonably
     practicable;

(d)  Any representation or warranty herein or in the Acquisition Agreement made
     by Borrower proves to have been untrue in any material respects as of the
     date as of which the facts therein set forth were stated or certified, and
     corrective measures, satisfactory to Lender with respect as of the date as
     of which the facts therein set forth were stated or certified, and
     corrective measures, satisfactory to Lender with respect thereto shall not
     have been taken within 10 days after notice thereof to Lender; provided, if
     compliance is not possible within 10 days, default shall occur upon failure
     within 10 days to take steps that will produce compliance as is reasonably
     practicable;

(e)  Borrower shall file a voluntary petition in bankruptcy or a voluntary
     position seeking reorganization, or shall file an answer admitting the
     jurisdiction of the court and any material allegations of an involuntary
     petition filed pursuant to any act of Congress relating to bankruptcy or to
     any act purporting to be amendatory thereof, or shall be adjudicated
     bankrupt, or shall make an assignment for the benefit of creditors, or
     shall apply for or consent to the appointment of ANY receiver or trustee
     for Borrower, or of all or any substantial portion of its property, or
     Borrower shall make an assignment to an agent authorized to liquidate any
     substantial part of its assets;

(f)  An order shall be entered pursuant to any act of Congress relating to
     bankruptcy or to any act purporting to be amendatory thereof approving an
     involuntary petition seeking reorganization of Borrower, or an order of any
     court shall be entered appointing any receiver or trustee of or for
     Borrower, or any receive or trustee of all or any substantial portion of
     the property of Borrower, or a writ or warrant of attachment or any similar
     process shall be issued by any court against all or any substantial portion
     of the property of Borrower, and such order approving a petition seeking
     reorganization or appointing a receiver or trustee is not vacated or
     stayed, or such writ, warrant of attachment, or similar process is not
     released or bonded within 60 days after its entry or levy; or

(g)  The rendering against the Borrower of final judgment for the payment of
     money in excess of $25,000 and failure of the Borrower to appeal therefrom
     (or from the order, decree, or process pursuant to which such judgment was
     granted, passed, entered, or affirmed) and obtain a stay of execution
     thereof within the period prescribed by law for appeal, or to have such
     judgment discharged and satisfied within 60 days after the expiration of
     such period or of the period of any such stay, whichever shall later occur.

3.2  Procedure on Default. Upon the occurrence of an event of default, and at
     any time thereafter, Lender may elect to declare the entire Note
     immediately due and payable.

(a)  In the event of default in the payment of said Note when due or declared
     due, Lender shall have all the rights and remedies of a secured party and
     shall be entitled to avail itself of all such other rights and remedies
     that may now or hereafter exist at law or in equity for the
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     security interest created hereby and resort to any remedy provided
     hereunder or provided by the Illinois Uniform Commercial Code, or by any
     other law of the state of Illinois, shall not prevent the concurrent or
     subsequent employment of any other appropriate remedy or remedies; and

(b)  The requirement of reasonable notice to Borrower of the time and place of
     any public sale of the security or of the time after which any private
     sale, or any other intended disposition thereof is to be made, shall be met
     if such notice is mailed, postage prepaid, to Borrower at the address of
     such party designated below, at least 30 days before the date of any public
     or private sale or other disposition is to be made.

3.3  Defaults Upon Prior Indebtedness. Upon the default by Borrower of any term,
     covenant, or condition required to be performed by if on any priority
     secured indebtedness or the receipt by Borrower from any such priority
     secured creditor of notice of any default under such indebtedness, whether
     or not repayment of the indebtedness is accelerated, Borrower shall
     promptly advise Lender in writing of the nature and amount of default and
     of the action, if any, threatened by such priority secured creditor.
     Notwithstanding the Borrower's obligation to cure any and all such
     defaults, Lender may, but shall not be obligated to do so, in the name,
     place, and stead of Borrower and, in the case of such curative efforts by
     Lender, succeed to all of the rights, remedies, and security of such
     priority creditor.

4.   Attorneys' Fees. If this Note is placed with an attorney for collection, or
     is suit be instituted for collection, or is any other remedy permitted by
     law is pursued by Lender, because of any default in the terms and
     conditions herein, then in such event, the undersigned agrees to pay
     reasonable attorneys' fees, costs, and other expenses incurred by Lender in
     so doing.

5.   Governing Law. This Master Note shall be governed by and construed and
     enforced in accordance with the laws of the state of Illinois.

6.   Security Interest. Borrower shall execute a Security Agreement and an
     Escrow Agreement wherein Borrower shall grant to Lender a security interest
     in the Collateral as defined in the Interim Loan agreement, sufficient to
     secure the obligation created hereunder, which agreements shall be made a
     part of the Interim Loan Agreement and this Note and incorporated herein by
     this reference.

                                         BORROWER:

                                         CHICAGO MAP CORPORATION
                                         an Illinois corporation



                                         By:   /s/   John B. McLean
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                                         Its Duly Authorized Representative