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                                                                   Exhibit 10.18

                             SUBSCRIPTION AGREEMENT


JMAR Industries, Inc.
3956 Sorrento Valley Boulevard
San Diego, California 92121

Gentlemen:


1. Pursuant to the terms of the offer contained in the Confidential Private
Offering Memorandum dated October 1, 1997 (said Memorandum, including the
exhibits and attachments thereto, being hereinafter called the "Memorandum"),
the undersigned hereby tenders this subscription and applies for the purchase of
the number of Units set forth on the signature page of this agreement, each Unit
consisting of four shares of Common Stock and a Warrant to purchase one share of
Common Stock, at $4.40 per share, of JMAR Industries, Inc. (the "Company"), at a
purchase price of $13.60 per Unit. The minimum subscription has been established
at $25,000.00 (U.S.) (i.e, approximately 1,838 Units), but investments for less
than the minimum may be made and partial Units may be purchased in the
discretion of Baytree Associates, Inc. (the ?Placement Agent?). Together with
this Subscription Agreement, the undersigned is delivering to the ?Globe Trust,
as Escrow Agent for JMAR Industries, Inc.? a check in the full amount of the
purchase price for the Units which it is subscribing for pursuant hereto or
funds by wire transfer in accordance with the instructions provided herewith.

               2. Representations and Warranties. In order to induce the Company
to accept this subscription, the undersigned hereby represents and warrants to,
and covenants with, the Company as follows:

                      (i) The undersigned has received and carefully reviewed
               the Memorandum, and except for the Memorandum, the undersigned
               has not been furnished with any other materials or literature
               relating to the offer and sale of the Units;

                      (ii) The undersigned has had a reasonable opportunity to
               ask questions of and receive answers from the Company concerning
               the Company and the offering, and all such questions, if any,
               have been answered to the full satisfaction of the undersigned;

                      (iii) The undersigned has such knowledge and expertise in
               financial and business matters that the undersigned is capable of
               evaluating the merits and risks involved in an investment in the
               Units as described in the Memorandum;



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                      (iv) The Confidential Purchaser Questionnaire being
               delivered by the undersigned to the Company simultaneously
               herewith is true, complete and correct in all material respects;
               and the undersigned understands that the Company has determined
               that the exemption from the registration provisions of the
               Securities Act of 1933, as amended (the "Act"), relating to
               non-public offerings is applicable to the offer and sale of the
               Units, based, in part, upon the representations, warranties and
               agreements made by the undersigned herein and in the Confidential
               Purchaser Questionnaire referred to above;

                      (v) Except as set forth herein and in the Memorandum, no
               representations or warranties have been made to the undersigned
               by the Company or any agent, employee or affiliate of the Company
               and in entering into this transaction the undersigned is not
               relying upon any information, other than that contained in the
               Memorandum and the results of independent investigation by the
               undersigned;

                      (vi) The undersigned understands that (a) the Common Stock
               and the Common Stock issuable upon exercise of the Warrants have
               not been registered under the Act or the securities laws of any
               state, based upon an exemption from such registration
               requirements for non-public offerings pursuant to Regulation D
               under the Act and exemptions contained in applicable state laws;
               (b) the Units and the securities comprising the Units are and
               will be "restricted securities", as said term is defined in Rule
               144 of the Rules and Regulations promulgated under the Act; (c)
               the Units and the securities comprising the Units may not be sold
               or otherwise transferred unless they have been first registered
               under the Act and all applicable state securities laws, or unless
               exemptions from such registration provisions are available with
               respect to said resale or transfer; (d) other than as set forth
               in the Registration Rights Agreement, the Company is under no
               obligation to register the Units or the securities comprising the
               Units under the Act or any state securities laws, or to take any
               action to make any exemption from any such registration
               provisions available; and (e) the Common Stock and Warrants will
               bear a legend to the effect that the transfer of the securities
               represented thereby is subject to the provisions hereof;

                      (vii) The undersigned is acquiring the Units solely for
               the account of the undersigned, for investment purposes only, and
               not with a view towards the resale or distribution thereof;

                      (viii) The undersigned will not sell or otherwise transfer
               any of the Common Stock or the Common Stock issuable upon
               exercise of the Warrants or any interest therein, unless and
               until (a) said securities shall have first been registered under
               the Act and all applicable state securities laws; or (b) the
               undersigned shall have first delivered to the Company a written
               opinion of counsel (which counsel and opinion (in form and
               substance) shall be reasonably

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               satisfactory to the Company), to the effect that the proposed
               sale or transfer is exempt from the registration provisions of
               the Act and all applicable state securities laws;

                      (ix) The undersigned has full power and authority to
               execute and deliver this Subscription Agreement and to perform
               the obligations of the undersigned hereunder; and this
               Subscription Agreement is a legally binding obligation of the
               undersigned in accordance with its terms; and

                      (x) The undersigned is an "accredited investor," as such
               term is defined in Regulation D of the Rules and Regulations
               promulgated under the Act and as set forth in the Confidential
               Purchaser Questionnaire.

               3. The undersigned understands that this subscription is not
binding upon the Company until the Company accepts it, which acceptance is at
the sole discretion of the Company together with the Placement Agent and is to
be evidenced by the Company's execution of this Subscription Agreement where
indicated. This Subscription Agreement shall be null and void if the Company
does not accept it as aforesaid.

               4. The undersigned understands that the Company, with the
concurrence of the Placement Agent, may in its sole discretion, reject this
subscription and, in the event that the offering to which the Memorandum relates
is over-subscribed, offer partial Units or reduce this subscription in any
amount and to any extent, whether or not pro rata reductions are made of any
other investor's subscription.

               5. The undersigned agrees to indemnify the Company and hold it
harmless from and against any and all losses, damages, liabilities, costs and
expenses which it may sustain or incur in connection with the breach by the
undersigned of any representation, warranty or covenant made by it herein.

               6. Neither this Subscription Agreement nor any of the rights of
the undersigned hereunder may be transferred or assigned by the undersigned.

               7. This Subscription Agreement (i) may only be modified by a
written instrument executed by the undersigned and the Company; (ii) sets forth
the entire agreement of the undersigned and the Company with respect to the
subject matter hereof; (iii) shall be governed by the laws of the State of
California applicable to contracts made and to be wholly performed therein; and
(iv) shall inure to the benefit of, and be binding upon the Company and the
undersigned and its respective heirs, legal representatives, successors and
assigns.

               8. Unless the context otherwise requires, all personal pronouns
used in this Subscription Agreement, whether in the masculine, feminine or
neuter gender, shall include all other genders.



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               9. All notices or other communications hereunder shall be in
writing and shall be deemed to have been duly given if delivered personally or
mailed by certified or registered mail, return receipt requested, postage
prepaid, as follows: if to the undersigned, to the address set forth in the
Confidential Purchaser Questionnaire referred to above; and if to the Company,
to JMAR Industries, Inc., 3956 Sorrento Valley Boulevard, San Diego, California
92121, Attention: Dennis Valentine -- or to such other address as the Company or
the undersigned shall have designated to the other by like notice.

               IN WITNESS WHEREOF, the undersigned has executed this
Subscription Agreement this 3rd day of November, 1997.




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                                 SIGNATURE PAGE


Organization Signature:                     Individual Signature:

Banque Edouard Constant SA
-------------------------------------       ----------------------------
Print Name of Subscriber


By: /s/J.G. Mallet /s/B. Pellissier
-------------------------------------       ----------------------------
                                            Signature(s)


    Legal Adviser
-------------------------------------       ----------------------------
    Print Name and Title of                 Print Name(s)
    Person Signing


-------------------------------------       ----------------------------
                                            Print Name(s)


Number of Units Subscribed for:   250,000
                                ----------


                   (Please print information below exactly as
              you wish it to appear in the records of the Company)


-------------------------------------       ----------------------------
Name and capacity in which subscription is  Social Security Number of Individual
made -- see below for particular            or other Taxpayer I.D. Number
requirements

Address:                                    Address for notices if different:


-------------------------------------       ----------------------------
Number and Street                                  Number and Street

-------------------------------------       ----------------------------
City          State          Zip Code       City       State   Zip Code


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Please indicate form of ownership (if applicable):


--------------------------------        ----------------------------------------
TENANTS-IN-COMMON                       JOINT TENANTS WITH RIGHT OF SURVIVORSHIP
(Both Parties must sign above)         (Both Parties must sign above)



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                           ACCEPTANCE OF SUBSCRIPTION

                              JMAR INDUSTRIES, INC.


        The foregoing subscription is hereby accepted by JMAR Industries, Inc.
this 7th day of November, 1997, for 250,000 Units.

                                            JMAR INDUSTRIES, INC.


                                            By: /s/John S. Martinez
                                               ---------------------------------
                                               Name:      John S. Martinez
                                               Title:     Chairman & CEO


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