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                                                            EXHIBIT 10.(XXXVIII)

                      (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 ("Subscription Agreement"),  whereby TiNV1
has agreed to  subscribe  initially  for Five  Million,  Five  Hundred  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. We acknowledge and agree that a material  consideration for TiNV1's execution
and delivery of the  Subscription  Agreement is the issuance to TiNV1 of options
to  acquire  70,000,000  shares  of  common  stock  pursuant  to the  terms  and
conditions of the Stock Option  Agreement  that is attached as an exhibit to the
Subscription  Agreement.  We further acknowledge and agree that the Stock Option
Agreement   is  subject  to  the   approval   of  the   Company's   shareholders
("Shareholders'  Approval")  to: (a) amend  this  Corporation's  certificate  of
incorporation  to  increase  the  Company's  number  of  authorized   shares  to
250,000,000,  and (b) approve the Stock Option Agreement. We further acknowledge
that if the Company is unable to obtain the Shareholders' Approval, then you may
elect to rescind the  Subscription  Agreement or enforce the remedy described in
paragraph 2 below.

2. If the Company is unable to obtain the Shareholders' Approval within 150 days
of the date of this letter, then upon your election and your termination of your
rescission rights as provided above, both of which shall occur within 30 days of
such 150 days, the undersigneds hereby agree, without any further consideration,
to:  (a) assign and  transfer  to TiNV1 all our  respective  right,  title,  and
interest, in and to all securities,  including, but not limited to common shares
of the Company, that we directly or indirectly own ("Shares"), excluding options
to acquire the Company's securities, and (b) cancel and waive any further rights
that we have pursuant to any options to acquire the Company's securities.


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3. We represent and warrant to you that until the later of: (a) the  Shareholder
Approval,  or (b) our  transfer of Shares to you pursuant to paragraph 2, in the
event you elect such  remedy as  provided  above,  that all of our Shares  shall
remain free and clear of any lien or  encumbrance,  and shall not be transferred
or assigned in any manner.

4. The undersigned  acknowledges and agrees that: (a) the potential  transfer of
our  Shares to TiNV1 and  cancellation  of our stock  options  are  intended  to
provide  voting  and  other  intangible  benefits  to TiNV1 in  addition  to the
economic  benefit of owning the Shares if the  Shareholders'  Approval  does not
occur, and (b) a breach of the undersigned's  obligations hereunder would result
in irreparable harm to TiNV1,  which would not be adequately  compensated solely
by an award of money damages. The undersigned  therefore agrees that TiNV1 shall
be  entitled  to  injunctive  relief  to  enforce  specific  performance  of our
obligations  under this  agreement,  and we  expressly  consent and agree to the
granting of such injunctive  relief, and further waive any requirement for TiNV1
to post any bond or other security in connection  with obtaining such injunctive
relief.

5. 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.

6. 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.

7. 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,

                                    /s/ Christopher D. Michaels
                                    ----------------------------
                                       Christopher D. Michaels

                                    /s/ Jeffrey S. Kramer
                                    ---------------------------
                                       Jeffrey S. Kramer

ACKNOWLEDGED AND AGREED:

DATED: As of August 28, 1998         TiNV1, INC.

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