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                                                                  EXHIBIT 10.15

                              REAL ESTATE MORTGAGE


 THIS INDENTURE WITNESSETH: That Bioanalytical Systems, Inc., (hereinafter
referred to as "Mortgagor") of Tippecanoe County, State of Indiana MORTGAGE AND
WARRANT to BANK ONE, LAFAYETTE, NA, a national banking association with its
main banking office at 201 Main Street, Lafayette, IN 47901 (hereinafter
referred to as "Bank"), the following described real estate (hereinafter
referred to as "Mortgaged Premises") in Tippecanoe County, State of Indiana:

 Lot numbered Two (2) in the Replat of Part of Lot 1 McClure Park Subdivision,
 Part Two, as per plat thereof dated March 30, 1983 and recorded April 18, 1983
 in Plat Cabinet C, Slide C-59, in the Office of Recorder, Tippecanoe County,
 Indiana.  Located in the City of West Lafayette, Wabash Township, Tippecanoe
 County, Indiana.

 Lot 1 in Replat of Part of Lot 1 McClure Park Subdivision, Part Two per the
 plat thereof dated March 30, 1983, recorded April 18, 1983, Plat Cabinet C,
 Slide C-59, Document #8302918 in the Office of the Recorder of Tippecanoe
 County, Indiana.  Located in the City of West Lafayette, Wabash Township,
 Tippecanoe County, Indiana.

together with all rights, privileges, interest easements, hereditaments,
appurtenances, fixtures and improvements now or hereafter belonging,
appertaining, attached to, or used in connection with, the Mortgaged Premises,
and the rents, issues, income and profits thereof.

 This Mortgage is given to secure the performance of the provisions and the
payment of:

  A.  That certain promissory note from Bioanalytical Systems, Inc. to Bank
      dated July 19, 1996 in the principal sum of Four Million Seven Hundred
      Twenty Thousand and no/l00 ($4,720,000.00) with interest as therein
      stated and with a final maturity date of January 19, 1998, together with
      any future modifications, extensions, and renewals thereof, and any and
      all notes or other instrument(s) given in substitution therefore and/or
      replacement thereof (such note(s) or other instruments all included in
      the term "note"); and

  B.  Any other indebtedness now or hereafter owing Bank by the Mortgagor when
      evidenced by a promissory note(s), guaranty, hypothocation(s), or any
      other instrument(s) reciting that they are secured by this Mortgage.

 In all cases the debt secured hereby includes advancements to protect the
security, costs of collection and reasonable attorney's fees.  This Mortgage
shall secure payment of the note(s) whether the entire amount shall have been
advanced to the Mortgagor at the date hereof or at a later date, or having been
advanced, shall have been repaid in part and further advances made at a later
date.  The note(s) and this Mortgage, including the terms of repayment thereof,
may from time to time be modified or amended in writing to include any future
advance or advances whether or not related to 


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the original advances together with the specified interest thereon.   It is
agreed that this Mortgage shall secure the unpaid balance of loans or advances
made by Bank not to exceed $4,720,000.00  in the aggregate and exclusive of
interest, advances to protect the security, costs of collection and reasonable
attorney's fees.  If the unpaid balance at any time exceeds such amount, then
this Mortgage shall secure that portion of the outstanding balance which does
not exceed such amount.
        
 The Mortgagor, jointly and severally if more than one, covenant and agree with
the Bank that:

 1.  Mortgagor will pay when due all indebtedness secured hereby, on the dates
and in the amounts, respectively, as provided in any note or other evidence of
indebtedness secured by this Mortgage and in this Mortgage, with attorneys'
fees, and without relief from valuation or appraisements laws.


 2.  Mortgagor will not permit any lien of mechanics or materialmen to attach
to the Mortgaged Premises.


 3.  Mortgagor will keep the Mortgaged Premises in good repair, and will not
commit or permit waste thereon, and will pay when due all taxes and assessments
levied or assessed against the Mortgaged Premises or any part thereof.  The
Bank may enter upon and inspect the Mortgaged Premises at any reasonable time.


 4.  Mortgagor will procure and maintain in effect at all times adequate
insurance from reliable insurance companies acceptable to the Bank against loss
or destruction of the Mortgaged Premises on account of fire, windstorm and such
other hazards and in such amounts as the Bank may require from time to time,
and all such policies of insurance shall contain proper clauses making all sums
recoverable upon such policies payable to the Bank and to the Mortgagor as
their respective interests may appear; all such policies of insurance and all
abstracts of title or title insurance policies with respect to the Mortgaged
Premises shall be delivered to and retained by the Bank until the indebtedness
secured hereby is fully paid.


 5.  Bank may, at its option, advance and pay all sums necessary to protect and
preserve the security intended to be given by this Mortgage; and all sums so
advanced and paid by Bank shall become a part of the indebtedness secured
hereby and shall bear interest from date of payment at the same rate or rates
as the principal indebtedness evidenced by any note or other evidence of
indebtedness; and such sums may include, but not by way of limitation, (i)
insurance premiums, taxes and assessments, and liens which maybe or become
prior and senior to this Mortgage as a lien on the Mortgaged Premises, or any
part thereof, (ii) the cost of any title insurance, surveys, or other evidence
which in the discretion of Bank may be required to establish and preserve the
lien of this Mortgage; (iii) all costs, expenses and attorneys' fees incurred
by Bank in respect of any and all legal or equitable actions which relate to
this Mortgage or to the Mortgaged Premises, during the existence of the
indebtedness secured by this Mortgage; and (iv) the cost of any repairs deemed
necessary and advisable by Bank to be made to the Mortgaged Premises.

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 6.  Bank shall be subrogated to the rights of the holder of each lien or claim
paid with monies secured hereby; and Bank at its option, an on such terms as it
may desire, may extend the time of payment of any part or all of the
indebtedness secured hereby without in any way impairing the lien of its
Mortgage or releasing Mortgagor or any of them from liability under this
Mortgage or under any note or other evidence of indebtedness.


 7.  If any default shall occur in the payment of any of the indebtedness
secured hereby, or in the performance of any covenant or agreement or Mortgagor
in the loan commitment(s), loan agreement(s) or hereunder, or if Mortgagor
shall abandon the Mortgaged Premises, or shall be adjudged bankrupt, or if a
trustee or receiver shall be appointed for Mortgagor or for any part of the
Mortgaged Premises, then and in any such event all indebtedness secured hereby
shall, at the option of Bank, become immediately due and payable without notice
to mortgagor, and this Mortgage may be foreclosed accordingly.  The waiver by
Bank of any default of Mortgagor shall not operated as a waiver of other
defaults.  Notice by Bank of its intention to exercise any right or option
hereunder is hereby expressly waived by Mortgagor, and any one or more of
Bank's rights or remedies hereunder may be enforced successively or
concurrently.  Any delay in enforcing any such right or remedy shall not
prevent its later enforcement while Mortgagor shall be in default hereunder.
In the event of the foreclosure of this Mortgage, all abstracts of title and
all title insurance policies for the Mortgaged Premises shall become the
absolute property of Bank.

 8.  Unless otherwise agreed in writing, the Bank shall be entitled to all
compensation, awards, damages, claims, rights of action and proceeds of, or on
account of, any damage or taking through condemnation or eminent domain
regarding the Mortgaged Premises, with any excess over all sums due hereunder
paid to Mortgagor.


 9.  Mortgagor shall not sell, convey, transfer, lease or further encumber any
interest in or any part of the Mortgaged Premises, nor shall a voluntary sale,
pledge or other transfer of the beneficial interest in Mortgagor be effected
without the prior written consent of the Bank having been obtained to the
purchase, transfer, lease or pledge, to the purchaser, transferee, lessee or
pledgee and to the form and substance of any instrument evidencing any such
purchase, transfer, lease or pledge.  Any such sale, conveyance, transfer,
pledge, lease or encumbrance made without the Bank's prior written consent
shall be void.


 10.  Upon default hereunder, the Bank, to the extent permitted by law and
without regard to the value or occupancy of the Mortgaged Premises, shall be
entitled as a matter of right if it so elects to the appointment of a receiver
to enter upon and take possession of the Mortgaged Premises and to collect all
rents, revenues, issues, income, and profits thereof and apply the same as the
court may direct.


 11.  Mortgagor has not actual or constructive knowledge of the existence,
release, or threatened release at the Mortgaged Premises of any substance
deemed toxic or hazardous under any applicable federal, state, or local laws.
And that the Mortgagor will not allow or cause the release or threatened
release of hazardous or toxic substances or waste on the Mortgaged Premises and

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agrees to indemnify and hold the Bank harmless from all costs and damage caused
by Mortgagor, or those claiming by and through Mortgagor, releasing or dumping
any such hazardous waste.  Bank may, at its option, advance all sums necessary
to protect and preserve the security, which sums shall become a part of the
indebtedness, including the cost of any necessary environmental inspection
performed on the Mortgaged Premises; the cost of cleaning up any release or
threatened release of hazardous or toxic material or waste at the Mortgaged
premises.  And Mortgagor is, and shall remain, in compliance with all
environmental laws and shall not use, store, or dispose of hazardous
substances, other than has been disclosed in writing to the Bank at the time
the loan is made.  And Mortgagor shall immediately inform the Bank of any
notices, complaints, governmental investigations, fines or penalties imposed
for noncompliance in regard to environmental statutes.


 12.  No rights, power or remedy conferred upon or reserved to the Bank by any
note, this Mortgage or any other instrument is exclusive of any other right,
power, or remedy but each and every such right, power, and remedy shall be
cumulative and concurrent and shall be in addition to any other right, power,
and remedy given hereunder or under a note or any other instrument securing the
note, or now or hereafter existing at law, in equity or by statute.


 13.  If any term or provision of the note or this Mortgage shall be deemed
invalid, illegal or unenforceable in any respect, the validity of the remaining
terms or provisions shall not be affected or prejudiced; and if the application
of any term or provision of the note or this Mortgage shall be deemed invalid,
illegal or unenforceable, the application of the remaining terms or provisions
shall not be affected or prejudiced unenforceable, the application of the
remaining terms or provisions shall not be affected or prejudiced.


 14.  All rights and obligations of Mortgagor hereunder shall extend to and be
binding upon the several heirs, representatives, successors and assigns of
Mortgagor, and shall inure to the benefit of Bank, its successors and assigns.
In the event this Mortgage is executed by more than one person, corporation, or
other entity, the work "Mortgagor" as used herein shall be construed to mean
and include each of them, and the terms and provisions of this Mortgage
construed accordingly.


 15.  This Mortgage is ___ x ___ is not _____ a "purchaser money mortgage".

 IN WITNESS WHEREOF, the Mortgagor has executed this instrument on this 19th
day of July, 1996.

                        BIOANALYTICAL SYSTEMS, INC.



                         By:   \S\LINA L. REEVES-KERNER
                               --------------------------------
                               Lina L. Reeves-Kerner
                               Vice President

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STATE OF INDIANA                     )
                               SS:   )               (Individual Acknowledgment)
COUNTY OF TIPPECANOE                 )


        Before me, a Notary Public in and for said County and State, personally
appeared _______________________________________________________ who
acknowledged the execution of the above and foregoing Real Estate Mortgage
this _____ day of ________________, 19___.

My Commission Expires:                         Signature:
                                                         -----------------------

- ----------------------                         Printed:
                                                         -----------------------
                                                         Notary Public
County of Residence:

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STATE OF INDIANA                     )
                               SS:   )               (Individual Acknowledgment)
COUNTY OF TIPPECANOE                 )


         Before me, a Notary Public in and for said County and State,
personally appeared Lina L. Reeves-Kerner, the Vice President, respectively of
Bioanalytical Systems, Inc. who acknowledged the execution of the above and
foregoing Real Estate Mortgage for and on behalf of said corporation this 19th
day of July, 1996.

My Commission Expires:                         Signature: \S\BECKY MAURER
                                                          ------------------
                                               Printed:
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                                                          Notary Public

County of Residence:


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This instrument prepared by: Murray N. Marshall             
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