Exhibit 10.27



                                 GUARANTEE
                                 ---------

          WHEREAS, Fleet Bank, N.A., and The Chase Manhattan Bank
(collectively, the "Banks") have entered into a Credit Agreement (the
"Credit Agreement"), dated July 31, 1996, with Veeco Instruments Inc. (the
"Debtor"); and

          WHEREAS, under the terms of the Credit Agreement, the Banks have
each agreed to extend credit to the Debtor, which indebtedness will be
evidenced by certain promissory notes of the Debtor (the "Notes"), dated as
of July 31, 1996, in the principal amounts as follows:

          Fleet Bank, N.A. - $18,000,000
          The Chase Manhattan Bank - $12,000,000; and

          WHEREAS, the undersigned (the "Guarantor") is a direct or
indirect subsidiary of the  Debtor and has derived or will derive direct
benefit from the extension of credit to the Debtor; and

          WHEREAS, the Banks will not extend such credit unless, among
other conditions, the undersigned Guarantor shall have executed and
delivered this Guarantee;

          NOW, THEREFORE, in consideration of the Banks extending such
credit to the Debtor and other benefits accruing to Guarantor, the receipt
and sufficiency of which are hereby acknowledged, Guarantor hereby makes
the following representations and warranties to the Banks and hereby
covenants and agrees with the Banks as follows:

          1.  Guarantor irrevocably and unconditionally guarantees to the
Banks (i) timely payment in full by Debtor to Banks of all payments due
pursuant to the Notes (it being understood that this is a guarantee of
payment and not of collection), and (ii) timely payment and/or performance,
as applicable, of all other payment and performance obligations of Debtor
pursuant to the Notes, the Credit Agreement and all other documents and
instruments executed in connection therewith, or pursuant to any amendment,
modification or supplement to any of the foregoing (all of the foregoing
under clauses (i) and (ii) being collectively referred to as the
"Guaranteed Obligations").  If Debtor shall default in payment of any
amount due pursuant to the Notes beyond any applicable grace period or
otherwise default beyond any applicable grace period in the performance of
the Guaranteed Obligations, Guarantor irrevocably and unconditionally
agrees to pay to the Banks upon demand the amount in default (it being
understood, however, that a non-payment may result in the acceleration of
all indebtedness and a demand for payment in full by the Guarantor under
the Guarantee).  Guarantor understands, agrees and confirms that the Banks
may enforce this Guarantee up to the full amount of the Guaranteed
Obligations owing against the Guarantor without proceeding against the
Debtor, against any security for the Guaranteed Obligations or against any
other guarantor under any other guarantee covering the Guaranteed
Obligations.







          2.  Guarantor hereby acknowledges the Guaranteed Obligations and
hereby expressly waives: (i) presentment and demand for payment of the
principal of or interest thereon or any other sums of any nature whatsoever
with respect thereto, (ii) notice of acceptance of this Guarantee, or of
the extension of credit to the Debtor, (iii) notice of any default
hereunder or under any agreements between the Banks and the Debtor with
respect to the Guaranteed Obligations, and of all indulgences with respect
thereto, (iv) demand on the Debtor for observance or performance of, or
enforcement of any terms or provisions of any agreements between the Banks
and the Debtor with respect to the Guaranteed Obligations, (v) to the
maximum extent permitted by applicable law and except as otherwise provided
herein, the benefit of all laws now or hereafter in effect in any way
limiting or restricting the liability of Guarantor under this Guarantee,
including any and all right to stay of execution and exemption of property
in any action to enforce the liability of the Guarantor hereunder and (vi)
any other event or circumstance which may constitute a release of or
defense to the obligor(s) under the Guaranteed Obligations or the Guarantor
under this Guarantee.  In the event this Guarantee shall be enforced by
suit or otherwise, the Guarantor shall pay the Banks, on demand, for all
reasonable fees and expenses incurred by the Banks in connection therewith,
including, without limitation, the reasonable fees and expenses of the
Banks' counsel.

          3.  The Banks in their sole and absolute discretion, may at any
time and from time to time without the consent of, or notice to, Guarantor
without incurring responsibility to Guarantor, without impairing or
releasing the obligations of Guarantor hereunder, upon or without any terms
or conditions and in whole or in part (but in all events subject to the
applicable provisions of the Credit Agreement):

               (a)  by agreement with the Debtor, change the manner, place
or terms of payment of, and/or change or extend the time of payment of,
increase the amount of, or renew or alter any of the Guaranteed
Obligations, any security therefor, or any liability incurred directly or
indirectly in respect thereof, and the Guarantee herein made shall apply to
the Guaranteed Obligations as so changed, extended, increased, renewed or
altered; 

               (b)  exercise or refrain from exercising any rights against
Debtor or others or otherwise act or refrain from acting; 

               (c)  release, settle or compromise any of the Guaranteed
Obligations, any security therefor or any liability (including any of those
hereunder) incurred directly or  indirectly in respect thereof or hereof,
and may subordinate the payment of all or any part thereof to the payment
of any liability (whether due or not) of Debtor to creditors of Debtor
other than Guarantor; 

               (d)  consent to or waive any breach of, or any act, omission
or default under, the Credit Agreement or the Notes, or any of the
instruments or agreements referred to therein, or otherwise amend, modify
or supplement any of the foregoing;



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               (e)  agree to the substitution, exchange, release or other
disposition of all or any part of any property securing the Guaranteed
Obligations;

               (f)  make advances for the purposes of performing any term
or covenant contained in any agreement between the Banks and the Debtor
with respect to which the Debtor may be in default;

               (g)  assign or otherwise transfer all or any part of the
Guaranteed Obligations; and

               (h)  deal in all respects with the Debtor as if this
Guarantee were not in effect.

          4.  No invalidity, irregularity or unenforceability of all or any
part of the Guaranteed Obligations or of any security therefor shall
affect, impair or be a defense to this Guarantee, and this Guarantee is a
primary obligation of Guarantor.

          5.  This Guarantee is a continuing one and all liabilities to
which it applies or may apply under the terms hereof shall be conclusively
presumed to have been created in reliance hereon.  No failure or delay on
the part of the Banks (whether acting individually or through an agent), or
any of them, in exercising any right, power or privilege hereunder shall
operate as a waiver thereof, nor shall any single or partial exercise of
any right, power or privilege hereunder preclude any other or further
exercise thereof or the exercise of any other right, power or privilege. 
The rights and remedies herein expressly specified are cumulative and not
exclusive of any rights or remedies which the Banks (whether acting
individually or through an agent), or any of them, or any subsequent holder
of any Guaranteed Obligations would otherwise have.  No notice to or demand
on Guarantor in any case shall entitle Guarantor to any other or further
notice or demand in similar or other circumstances or constitute a waiver
of the rights of the Banks (whether acting individually or through an
agent), or any of them, or any holder of any Guaranteed Obligations to any
other or further action in any circumstances without notice or demand.

          6.  This is a guarantee of payment and not of collection, and the
liability of Guarantor under this Guarantee shall be primary, direct and
immediate, and not conditional or contingent upon pursuit by the Banks of
any remedies it may have against the Debtor with respect to the Guaranteed
Obligations whether pursuant to the terms thereof or by law, or against any
other person or entity or against any other collateral.  Without limiting
the generality of the foregoing, the Banks shall not be required to make
any demand on the Debtor, or to sell at foreclosure or otherwise pursue or
exhaust its remedies against the property securing the Debtor's obligations
for the Guaranteed Obligations or against the Debtor, or against any other
person or entity or against any other collateral whatsoever, before,
simultaneously with or after enforcing its rights and remedies hereunder
against the Guarantor.   Any one or more successive or concurrent actions
may be brought hereon against the Guarantor either in the same action, if
any, brought against the Debtor, or in separate actions, as often as the
Banks may deem advisable.



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          7.  Guarantor represents and warrants to the Banks that:

               (a)  It is a corporation duly organized, validly existing
and in good standing under the laws of the jurisdiction of its
incorporation and has all corporate power and authority to own all of its
properties and to carry on its business as presently conducted and as
contemplated by this Guarantee and has corporate power and authority to
execute and deliver this Guarantee and to perform its obligations
hereunder. 

               (b)  This Guarantee is and will be the legal, valid and
binding obligation of Guarantor enforceable in accordance with its terms
except to the extent that enforceability may be limited by bankruptcy,
insolvency, reorganization or other similar laws affecting the enforcement
of creditors' rights generally and by general principals of equity
(regardless of whether enforcement is sought in a proceeding brought in
equity or at law).  The execution, delivery and performance of this
Guarantee and such other agreements, documents and instruments and the
performance of the transactions contemplated hereunder have been and will
be duly and validly authorized and approved by the Board of Directors and
do not and will not require any consent or approval of any third party or
of the stockholders of Guarantor other than consents which have previously
been obtained.

               (c)  The execution and delivery of this Guarantee do not,
and the consummation of the transactions contemplated hereby will not,
constitute a violation of, and are not, and will not be, a default under or
conflict with the terms of the Certificate of Incorporation or By-laws of
Guarantor, or any contract, lease, indenture, agreement, order, judgment,
or decree to which it is a party or by which it is bound or to which any of
its assets are subject, which in any case or in the aggregate could have a
material adverse effect on its ability to carry out its obligations under
this Guarantee, and do not, and will not, violate or constitute a default
under any statute, rule, regulation, order or ordinance of any
governmental, judicial or arbitral body, which in any case, or in the
aggregate, could have a material adverse effect on its ability to carry out
its obligations under this Guarantee.

               (d)  Neither the execution, delivery or performance of this
Guarantee, nor the consummation of the transactions contemplated hereby,
requires Guarantor to obtain any consent, authorization, approval or
registration under any law, rule or regulation, other than as contemplated
hereby or as previously obtained.

               (e)  Other than as previously disclosed to the Banks in the
Credit Agreement, there is no suit, action or legal, administrative,
arbitration or other proceeding of any nature pending, or, to the knowledge
of Guarantor, threatened, against it which might affect the legality or
validity of this Guarantee, or the transactions contemplated hereby, and
there is not any factual basis known to it for any such suit, action or
proceeding.

          8.  This Guarantee shall be binding upon Guarantor and its
successors and assigns and shall inure to the benefit of the Banks and
their respective successors and permitted assigns.  



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This Guarantee may not under any circumstances be assigned by Guarantor to
any other person or entity without the express prior written consent of
each of the Banks.

          9.  Neither this Guarantee nor any provision hereof may be
changed, waived, discharged or terminated except with the written consent
of each of the Banks.

          10. In the event that either Bank shall receive any payments on
account of any of the Guaranteed Obligations, whether directly or
indirectly, and it shall subsequently be determined that such payments were
for any reason improper, or a claim shall be made against such Bank that
the same were improper, and such Bank pursuant to court order shall return
the same, Guarantor shall be liable, with the same effect as if the said
payments had never been paid to, or received by such Bank, for the amount
of such repaid or returned payments, notwithstanding the fact that they may
theretofore have been credited on account of the Guaranteed Obligations or
any of them.  Moreover, this Guarantee shall remain effective or be
reinstated, as the case may be, if at any time payment or performance, or
any part thereof, or any or all of the Guarantor's obligations under this
Guarantee is rescinded or must otherwise be restored or returned by the
Banks, or any of them, in connection with the insolvency, bankruptcy or
reorganization of the Guarantor or otherwise, all as though such payment or
performance had not been rendered.  Notwithstanding any compromise,
release, discharge, settlement, extension or adjustment of the Debtor's
obligations or any amendment, modification or stay of the Banks' rights
against the Debtor that may occur in any bankruptcy or reorganization case
or proceeding concerning the Debtor, whether or not assented to by the
Banks, Guarantor shall remain fully obligated to discharge the Guarantor's
obligations hereunder in accordance with the terms of this Guarantee in
effect on the date hereof.  Guarantor assumes all risks of a bankruptcy or
reorganization with respect to the Debtor.  In furtherance of this Section,
the Banks shall not otherwise indicate the satisfaction of the obligations
of the parties represented herein until the expiration of all applicable
bankruptcy-related periods of time during which the Debtor, the Guarantor
or any third party would have the right to commence a bankruptcy or
reorganization proceeding with regard to the Debtor or Guarantor.

          11.  All notices and other communications provided for under this
Guarantee and under any other document executed in connection herewith
shall be in writing (including telegraphic or telefax communications) and,
unless the party to be notified otherwise notifies the other party in
writing as provided herein, notices shall be given by telecopier, by
certified or registered mail or by recognized overnight delivery service. 
If such notice is delivered to Guarantor, such notice shall be addressed to
Guarantor at 602 East Montecito Street, Santa Barbara, California 93103,
telecopier (805)962-5163, Attn: Tim Stultz and, if to the Banks, at their
respective addresses listed on the signature pages of the Credit Agreement;
or as to each party, at such other address as shall be designated by such
party in a written notice to the other parties complying as to delivery
with the terms of this Section 10.  Notices shall be effective: (a) if
given by registered or certified mail, on the third day after deposit in
the mails with postage prepaid, addressed as aforesaid; (b) if given by
recognized overnight delivery service, on the business day following
deposit with such service, addressed as aforesaid; and (c) if given by
telecopy, when the telecopy is transmitted to the telecopy number, as
aforesaid; provided that all notices to the Banks shall be effective on
receipt.  



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          12.  This Guarantee and the rights and obligations of the Banks
and of the undersigned hereunder shall be governed and be construed in
accordance with the laws of the State of New York applicable to agreements
made and to be wholly performed in the State of New York.  Guarantor hereby
irrevocably submits to the jurisdiction of any New York State or United
States Federal Court sitting in Nassau, Suffolk or New York County over any
action or proceeding arising out of or relating to the Guarantee, and the
Guarantor hereby irrevocably agrees that all claims in respect of such
action or proceeding may be heard and determined in such New York State or
Federal court.  Guarantor irrevocably consents to service of any and all
process in any such action or proceeding by the mailing (by registered or
certified mail) of copies of such process to it at its address specified in
Section 11.  Guarantor agrees that a final judgment in any such action or
proceeding shall be conclusive and may be enforced in other jurisdictions
by suit on the judgment or in any other manner provided by law.  To the
extent permitted by applicable law, Guarantor further waives any objection
to venue in such State or Federal court and any objection to an action or
proceeding in such State or Federal court on the basis of forum non
                                                          ----- ---
conveniens.  Nothing in this Section shall limit the rights of the Banks to
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serve legal process in any other manner permitted by law or affect the
right of any Bank to bring any action or proceeding against Guarantor in
the courts of any other jurisdiction.  To the extent that Guarantor has or
hereafter may acquire immunity from jurisdiction of any court or from any
legal process with respect to itself or its property, Guarantor hereby
waives, to the extent permitted by applicable law, such immunity in respect
of their obligations hereunder.

          13.  THE PARTIES HERETO WAIVE ANY RIGHT TO A TRIAL BY JURY IN
CONNECTION HEREWITH TO THE EXTENT PERMITTED BY APPLICABLE LAW.

          IN WITNESS WHEREOF, Guarantor has caused this Guarantee to be
executed and delivered as of July 31, 1996.


                              THE GUARANTOR:


                              SLOAN TECHNOLOGY CORPORATION


                              By:   /s/ John F. Rein, Jr.
                                    ----------------------------
                                    Name:    John F. Rein, Jr.      
                                    Title:   Vice President



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