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                                                                 EXHIBIT 10.(XL)
                      (NEVADA MANHATTAN MINING LETTERHEAD)

August 28, 1998


TiNVl, Inc.
701 Ocean Avenue, Suite 108
Santa Monica, CA 90402

Gentlemen:

As an  inducement  to  TiNV1,  Inc.  ("TiNV1")  to enter  into the  Subscription
Agreement  dated as of August 28,  1998,  whereby  TiNV1 has agreed to subscribe
initially for Five Million,  Five Hundred and Fifty Thousand  (5,500,000) shares
of common stock  ("Subscription  Shares") of Nevada Manhattan Mining,  Inc. (the
"Company") for Five Hundred Thousand Dollars ($500,000.00) in capital, we hereby
agree to the following:

1. The  Board  of  Directors  of the  Company  will  immediately  institute  the
expansion of the Company's Board of Directors to a total of seven members.

2. Three  designees of TiNVl will upon such expansion be elected to the Board of
Directors of the Company.

3.  Thereafter,  three designees of TiNV1,  subject to increase or decrease,  as
provided below, will be included in management's slate of nominees for the Board
of Directors, and the Company will use its continuing best efforts to cause such
nominees  to be  elected to the Board.  The  number of TiNV1's  designees  shall
coincide with the number of directors  that TiNV1 is entitled to elect  pursuant
to paragraph 5 below.

4.  The  nominees  proposed  by  TiNV1  from  time to time  shall  possess  such
qualifications,  character and  reputation  as are  reasonably  appropriate  for
members of the Board of Directors of the Company.



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5. The Company  shall use its best efforts to create a class of preferred  stock
("Preferred  Stock")  which  possess   attributes,   rights,   privileges,   and
preferences,  which  are no  less  favorable  than  those  of the  common  stock
comprising the  Subscription  Shares.  Upon creation of the Preferred Stock, the
Company  shall  have the right to  exchange  the  common  stock  comprising  the
Subscription  Shares to Preferred  Stock on a one for one basis.  The  Preferred
Stock  shall  be  converted  back  into  common  stock  in  connection  with any
securities  registration of the subject  securities  under the Securities Act of
1933, as amended. TiNV1 shall be the sole holder of the Preferred Stock. Subject
to paragraph 6, TiNV1,  as holder of the Preferred  Stock,  voting as a separate
class,  shall be  entitled to elect three  Directors,  as long as the  Company's
Board of Directors  consists of seven  members.  If the number of members of the
Board of Directors increases (or decreases), then the Preferred Stock's right to
elect  Directors shall increase (or decrease) by one director for every increase
(or  decrease) of two members of the Board of  Directors.  For  example,  if the
Board of Directors is increased to nine members, then TiNV1 shall have the right
to elect four Directors.

6.  Notwithstanding  the  foregoing,  if  TiNV1's  beneficial  ownership  of its
Subscription  Shares,  whether in the form of common  stock or  Preferred  Stock
drops below  2,750,000 or  1,375,000  shares,  respectively,  adjusted for stock
dividends, merger, reorganization,  reclassification, stock splits, or any other
adjustment to the Company's capital structure, then the number of Directors that
TiNV1 shall have a right to nominate  and/or elect shall be reduced by one-third
and two-thirds,  respectively.  TiNV1's right to nominate and/or elect Directors
pursuant to paragraphs 3 and 5 shall  terminate if its  beneficial  ownership of
the Subscription Shares drops below 550,000 shares.

7. TiNV1 agrees to vote the maximum number of votes it has, per  candidate,  for
its designated director nominees unless the voting for the election of directors
is subject to  cumulative  voting.  If TiNVl's  nominees  are not elected to the
Board of Directors of the Company as provided in paragraphs 3 and 5, TiNV1 shall
have  the  right  for a  60-day  period  thereafter  to  put  any  or all of its
Subscription Shares,  whether common stock or Preferred Stock (collectively "Put
Stock"), as the case may be, then held by it to the Company at a price, which is
the greater  of: (a) the  purchase  price  therefor,  or (b) the  average  price
established by an independent  valuation as of the date of the corporate  action
giving rise to the valuation, by two of the present "Big 5" accounting firms, or
their sucessors.  TiNV1 and the Company shall each appoint an accounting firm to
perform a valuation of the Subscription  Shares ("Put Price") within thirty (30)
days of the event giving rise to the valuation.  The respective accounting firms
shall submit their  valuations  within  thirty (30) days after their  respective
appointment.  The Company shall  purchase the Put Stock from TiNV1 within thirty
(30) days of its receipt of the subject valuations from the accounting firms.


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8. If the Company has insufficient  legally  available funds to purchase the Put
Stock,  then the subject 60 day period shall not commence  until the Company has
legally available funds to purchase the Put Stock.  Further,  if the Company has
insufficient  legally available funds to purchase the Put Stock, then at TiNV1's
election,  it may sell its  Subscription  Shares to a bona fide third party. The
Company  shall issue a  promissory  note  ("Note")  to TiNV1 for the  difference
between  the Put Price and the third party sale.  The unpaid  principal  balance
shall bear interest at the rate of Bank of America's (or successor thereto) then
prime  rate  plus 2  points.  To the  extent  legally  permissible,  the  unpaid
principal  and accrued  interest  thereon  shall be fully  amortized and paid in
quarterly installments, with the first payment due and payable ninety days after
the date of the subject note. To the extent legally  permissible,  the remaining
unpaid  principal and accrued  interest  thereon shall be due and payable on the
second  anniversary  of the Note. The Company may prepay the balance of the note
without  penalty.  If Company is in default under the Note,  then TiNV1 shall be
entitled to recover its costs from the  Company,  including  attorneys'  fees to
enforce collection under the Note.

9. All  acquisitions  and  divestitures  by the  Company,  which  require  Board
approval,  and any issuances of securities to the Company's  debenture  holders,
must  initially be approved by 5 of the  Company's 7 Directors.  If the Board of
Directors  increases  in size,  then such  acquisitions,  divestitures,  and any
issuance to the debenture  holders must he approved by a super  majority vote of
two thirds of all members of the Board of Directors, and not a super majority of
a quorum of the Board of Directors.

10. The Company hereby agrees to enter into an employment  agreement with Daniel
Barton Pritchett of Los Angeles,  California,  for a period of not less than one
year. Mr.  Pritchett  will be designated as a Vice President of Financing,  with
his duties to encompass the financial  expansion of the Company,  and such other
duties as are designated by the Board of Directors.  Mr. Pritchett shall receive
compensation in the amount of $3,000.00 per month.


11. The Company  represents and warrants to TiNV1,  which shall survive  without
limitation, that it has the full right, power and authority to execute, deliver,
perform and comply with the terms and conditions of this agreement,  and that it
has taken all other  actions  necessary to enable the Company to comply with the
terms and  conditions  hereof.  This letter  agreement has been duly and validly
executed  and  delivered  by the Company and  constitutes  the valid and legally
binding obligation of the Company.


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12. This  Agreement  shall be governed by and construed in  accordance  with the
laws of the State of California.  If any provision of this Agreement is found by
a court of competent jurisdiction to be invalid, illegal, or unenforceable,  the
validity,  legality and enforceability of the remaining  provisions shall not be
affected thereby.

13.  If any  party  to this  Agreement  shall  commence  any suit or  action  to
interpret or enforce this Agreement,  the prevailing  party in such action shall
recover  such  party's  costs and  expenses  incurred in  connection  therewith,
including  attorneys' fees. 14. This Agreement shall inure to the benefit of and
be  binding  upon all of the  parties  hereto and their  respective,  executors,
administrators, successors and assigns.

                                   Sincerely,

                                  NEVADA MANHATTAN MINING
                                  INCORPORATED

                                        /s/ Christopher D. Michaels
                                  By:____________________________
                                     Christopher D. Michaels, President

                                        /s/ Jeffrey S. Kramer
                                  By:____________________________
                                      Jeffrey S. Kramer, Secretary

ACKNOWLEDGED AND AGREED:

       as of Aug. 28th
DATED:  ______________, 1998       TiNV1, INC.

                                        /s/ Tetsuo Kitagawa
                                   By:____________________________
                                        Tetsuo Kitagawa,
                                         President and Secretary