As filed with the Securities and Exchange Commission on June 9, 1999.
                              Registration No. 333-
-----------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549
                                 ---------------

                                    FORM S-8
                             Registration Statement
                                      Under
                           The Securities Act of 1933
                                 ---------------

                             THERMOQUEST CORPORATION
             (Exact name of registrant as specified in its charter)
                                 ---------------

      DELAWARE                                             77-0407461
(State or other jurisdiction of                       (I.R.S. Employer
 incorporation or organization)                 Identification Number)

                            2215 Grand Avenue Parkway
                            Austin, Texas 78728-3812
               (Address of Principal Executive Offices) (Zip Code)


             THERMOQUEST CORPORATION EMPLOYEES EQUITY INCENTIVE PLAN

                            (Full Title of the Plan)

                          Sandra L. Lambert, Secretary
                           Thermo Electron Corporation
                                 81 Wyman Street
                                 P. O. Box 9046
                        Waltham, Massachusetts 02454-9046
                     (Name and Address of Agent for Service)

                                  (781) 622-1000
          (Telephone Number, Including Area Code, of Agent For Service)

                                   Copies to:
                    Seth H. Hoogasian, Esq., General Counsel
                           Thermo Electron Corporation
                                 81 Wyman Street
                                 P. O. Box 9046
                        Waltham, Massachusetts 02454-9046

                                 ---------------

<PAGE>


                         CALCULATION OF REGISTRATION FEE


 TITLE OF                                         PROPOSED
SECURITIES         AMOUNT       PROPOSED          MAXIMUM            AMOUNT OF
  TO BE             TO BE       MAXIMUM           AGGREGATE        REGISTRATION
REGISTERED        REGISTERED    OFFERING        OFFERING PRICE          FEE
                                PRICE PER
                                  SHARE
  Common Stock,
 $.01 par value      500,000      $11.65625     $5,828,125(2)         $1,621
    per share       shares (1)       (2)


      In  addition,  pursuant to Rule 416(c) under the  Securities  Act of 1933,
this Registration Statement also covers an indeterminate number of shares of the
Company's  Common  Stock  issuable  in  connection  with  adjustments  under the
ThermoQuest  Corporation  Employees  Equity  Incentive  Plan to reflect  certain
changes in the Company's capital structure, including stock dividends or stock
splits.


(1)   Represents  additional  shares  available for grants under the ThermoQuest
      Corporation Employees Equity Incentive Plan as of June 9, 1999.

(2)   Estimated  solely  for  the  purpose  of  calculating  the  amount  of the
      registration  fee in accordance  with Rule 457(h) under the Securities Act
      of 1933.  The  Company  based  its  calculation  of the  proposed  maximum
      aggregate offering price on (1) the registration  herein of 500,000 shares
      of Common  Stock  and (2) the  average  of the high and low sales  prices,
      $11.6875 and $11.625,  respectively,  of the Company's Common Stock on the
      American  Stock  Exchange on June 8, 1999 as reported in the  consolidated
      reporting system.



<PAGE>




                                EXPLANATORY NOTE

      This Registration Statement is being filed pursuant to General Instruction
E of Form S-8 in order to register  additional  securities  of the same class as
other  securities  for  which a  registration  statement  relating  to the  same
employee benefit plan is effective.

      This Registration Statement relates to 500,000 shares of the Common Stock,
$.01 par value per share,  of  ThermoQuest  Corporation  (the  "Company"  or the
"Registrant"),  that are reserved for issuance under the ThermoQuest Corporation
Employees Equity Incentive Plan (the "Plan").  On November 24, 1998, the Company
filed an initial  registration  statement on Form S-8 (Reg.  No.  333-67853)  to
register  1,000,000  shares of Common Stock reserved for issuance under the Plan
(along  with other plans of the  Company).  The  addition  of this  Registration
Statement  brings the total number of shares  registered  for issuance under the
Plan to 1,500,000.  The contents of the previously filed registration  statement
are  incorporated  herein by  reference  except for the items that are set forth
below.  Pursuant to Instruction  E, this  Registration  Statement  contains such
information  required by Form S-8 that is not otherwise included in the previous
registration statement.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference.

      The Company is subject to the informational and reporting  requirements of
Sections 13(a),  13(c), 14 and 15(d) of the Securities  Exchange Act of 1934, as
amended (the "Exchange  Act"), and accordingly  files reports,  proxy statements
and other information with the Securities and Exchange Commission. The following
documents,  which  are on file with the  Commission,  are  incorporated  in this
Registration Statement by reference:

            (a)   The  Company's  Annual Report on Form 10-K for the fiscal year
                  ended January 2, 1999;

            (b)   The  Company's  Quarterly  Report on Form 10-Q for the quarter
                  ended April 3, 1999;

            (c)   The  description of the Common Stock which is contained in the
                  Company's  Registration  Statement on Form 8-A filed under the
                  Exchange Act, as amended from time to time.

      All reports or proxy statements filed by the Company under Sections 13(a),
13(c),  14 and 15(d) of the  Exchange  Act  after the date of this  Registration
Statement and before the filing of a post-effective  amendment  stating that all
securities  covered  by this  Registration  Statement  have been  sold,  or that
deregisters  all such securities  then remaining  unsold,  shall be deemed to be
incorporated by reference in this Registration Statement and to be a part hereof
from the respective dates of filing of such documents.
<PAGE>

Item 5.  Interests of Named Experts and Counsel.

      The  validity of the Common Stock  offered  hereby has been passed upon by
Seth H.  Hoogasian,  Esq.,  General Counsel of the Company.  Mr.  Hoogasian is a
full-time  employee of Thermo  Electron  Corporation  ("Thermo  Electron"),  the
majority  stockholder of Thermo Instrument  Systems Inc. ("Thermo  Instrument"),
which in turn is the majority  stockholder of the Company,  is an officer of the
Company,  Thermo  Instrument and Thermo  Electron,  and owns or has the right to
acquire  6,000 shares of Common Stock,  18,815 shares of the common stock,  $.10
par value per  share,  of Thermo  Instrument  and  348,828  shares of the common
stock, $1.00 par value per share, of Thermo Electron.

Item 6.  Indemnification of Directors and Officers.

     The Delaware  General  Corporation  Law and the  Company's  Certificate  of
Incorporation  and By-Laws  limit the  monetary  liability  of  directors to the
Company and to its stockholders and provide for indemnification of the Company's
officers and directors for  liabilities and expenses that they may incur in such
capacities.  In general,  officers and directors are indemnified with respect to
actions  taken in good faith in a manner  reasonably  believed  to be in, or not
opposed to, the best  interests of the Company and, with respect to any criminal
action or proceeding,  actions that the  indemnitee  had no reasonable  cause to
believe were unlawful. The Company also has indemnification  agreements with its
directors and officers that provide for the maximum  indemnification  allowed by
law.

      The Company has an  insurance  policy  which  insures  its  directors  and
officers against certain  liabilities which might be incurred in connection with
the performance of their duties.

Item 8.  Exhibits.

      The Exhibit Index  immediately  preceding the exhibits is attached  hereto
and incorporated herein by reference.

Item 9.  Undertakings.

      (a)   The undersigned Registrant hereby undertakes:

            (1) To file,  during any  period in which  offers or sales are being
made, a post-effective amendment to this registration statement:

                  (i)    To include any prospectus required by Section
     10(a)(3) of the Securities Act of 1933;
<PAGE>

                  (ii) To reflect in the  prospectus any facts or events arising
      after the effective date of the registration statement (or the most recent
      post-effective amendment thereof) which, individually or in the aggregate,
      represent  a  fundamental  change  in the  information  set  forth  in the
      registration  statement.  Notwithstanding  the foregoing,  any increase or
      decrease in volume of  securities  offered (if the total  dollar  value of
      securities  offered  would not exceed that which was  registered)  and any
      deviation from the low or high end of the estimated maximum offering range
      may be  reflected  in the form of  prospectus  filed  with the  Commission
      pursuant  to Rule 424(b) if, in the  aggregate,  the changes in volume and
      price  represent no more than 20 percent  change in the maximum  aggregate
      offering price set forth in the "Calculation of Registration Fee" table in
      the effective registration statement;

                  (iii) To include any material  information with respect to the
      plan  of  distribution  not  previously   disclosed  in  the  registration
      statement or any material change to such  information in the  registration
      statement.

      Provided,  however,  that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply
if the  information  required to be included in a  post-effective  amendment  by
those paragraphs is contained in periodic reports filed with or furnished to the
Commission  by the  Registrant  pursuant  to Section 13 or Section  15(d) of the
Securities  Exchange  Act of 1934  that are  incorporated  by  reference  in the
registration statement.

            (2) That,  for the purpose of  determining  any liability  under the
Securities Act of 1933, each such post-effective amendment shall be deemed to be
a new registration statement relating to the securities offered therein, and the
offering of such  securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (3)  To  remove  from  registration  by  means  of a  post-effective
amendment  any of the  securities  being  registered  which remain unsold at the
termination of the offering.

      (b) The undersigned  Registrant  hereby  undertakes  that, for purposes of
determining  any liability  under the Securities Act of 1933, each filing of the
Registrant's  annual report pursuant to Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 (and, where applicable,  each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of
1934) that is incorporated by reference in the  registration  statement shall be
deemed to be a new  registration  statement  relating to the securities  offered
therein,  and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.
<PAGE>

      (c)  Insofar  as  indemnification   for  liabilities   arising  under  the
Securities Act of 1933 may be permitted to directors,  officers and  controlling
persons of the Registrant  pursuant to the foregoing  provisions,  or otherwise,
the  Registrant  has been  advised  that in the  opinion of the  Securities  and
Exchange  Commission such  indemnification is against public policy as expressed
in the  Securities  Act and is,  therefore,  unenforceable.  In the event that a
claim for  indemnification  against such liabilities  (other than the payment by
the  Registrant  of  expenses  incurred  or  paid  by  a  director,  officer  or
controlling  person of the Registrant in the  successful  defense of any action,
suit or proceeding) is asserted by such director,  officer or controlling person
in connection with the securities being registered,  the Registrant will, unless
in the  opinion  of its  counsel  the matter  has been  settled  by  controlling
precedent,  submit to a court of appropriate  jurisdiction  the question whether
such  indemnification  by it is  against  public  policy  as  expressed  in  the
Securities Act and will be governed by the final adjudication of such issue.


<PAGE>


                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies  that it has  reasonable  grounds to believe  that it meets all of the
requirements  for  filing  on Form S-8 and has  duly  caused  this  Registration
Statement  to be  signed  on its  behalf  by  the  undersigned,  thereunto  duly
authorized, in the City of Franklin,  Commonwealth of Massachusetts, on this 9th
day of June, 1999.

                                   THERMOQUEST CORPORATION


                                   By:  /s/ Richard W.K. Chapman
                                        Richard W.K. Chapman
                                        President and Chief Executive
                                        Officer


                                POWER OF ATTORNEY

      Each of the undersigned Directors and Officers of ThermoQuest  Corporation
hereby appoints Theo Melas-Kyriazi,  Paul F. Kelleher, Kenneth J. Apicerno, Seth
H.  Hoogasian  and  Sandra L.  Lambert,  and each of them,  his true and  lawful
attorneys-in-fact  and agents,  with full power of substitution,  for him and in
his  name,  place  and  stead,  in any and all  capacities,  to sign any and all
amendments (including post-effective amendments) to this Registration Statement,
and to file the same, with all exhibits thereto, and all documents in connection
therewith,  with the  Securities  and Exchange  Commission,  granting  unto said
attorneys-in-fact  and agents,  and each of them, full power and authority to do
and perform each and every act and thing  requisite  and necessary to be done in
and about the  premises,  as fully to all  intents  and  purposes as he might or
could  do  in  person,   hereby   ratifying   and   confirming   all  that  said
attorneys-in-fact  and  agents  or any of them,  or their or his  substitute  or
substitutes, may lawfully do or cause to be done by virtue thereof.

      Pursuant  to  the  requirements  of  the  Securities  Act  of  1933,  this
Registration  Statement  has been signed below by the  following  persons in the
capacities and on the dates indicated:

Signature                          Title                              Date

                                   President and Chief Executive
/s/ Richard W.K. Chapman           Officer                          June 9, 1999
-------------------------
Richard W.K. Chapman
<PAGE>

/s/ Theo Melas-Kyriazi
-------------------------          Chief Financial Officer          June 9, 1999
Theo Melas-Kyriazi

/s/ Paul F. Kelleher               Chief Accounting Officer         June 9, 1999
-------------------------
Paul F. Kelleher

/s/ George N. Hatsopoulos          Director                         June 9, 1999
-------------------------
George N. Hatsopoulos

/s/ Frank Jungers                  Director                         June 9, 1999
-------------------------
Frank Jungers

                                   Chairman of the Board            June 9, 1999
/s/ Earl R. Lewis                  and Director
-------------------------
Earl R. Lewis

/s/ Anthony J. Pellegrino          Director                         June 9, 1999
-------------------------
Anthony J. Pellegrino

/s/ Michael E. Porter              Director                        June 9, 1999
---------------------
Michael E. Porter




<PAGE>


                                  EXHIBIT INDEX


Exhibit
Number            Description


5.1               Opinion of Seth H. Hoogasian, Esq.

23.1              Consent of Arthur Andersen LLP

23.2              Consent of Seth H. Hoogasian, Esq.
                  (contained in his opinion filed as
                  Exhibit 5.1).

24                Power of Attorney (see  signature  pages to this  Registration
                  Statement).



<PAGE>





                                                                    EXHIBIT 5.1



                             ThermoQuest Corporation
                            2215 Grand Avenue Parkway
                            Austin, Texas 78728-3812



                                                      June 9, 1999


ThermoQuest Corporation
2215 Grand Avenue Parkway
Austin, Texas 78728-3812

Re:   Registration Statement on Form S-8
      Relating to 500,000 Shares of the Common Stock,
      $.01 par value, of ThermoQuest Corporation

Dear Sirs:

      I am General Counsel to ThermoQuest  Corporation,  a Delaware  corporation
(the  "Company"),  and have acted as counsel in connection with the registration
under the  Securities  Act of 1933, as amended,  on Form S-8 (the  "Registration
Statement"), of 500,000 shares of the Company's Common Stock, $.01 par value per
share (the "Shares")  subject to the ThermoQuest  Corporation  Employees  Equity
Incentive Plan (the "Plan").

      I or a member of my legal staff have  reviewed the  corporate  proceedings
taken by the Company  with respect to the  authorization  of the issuance of the
Shares.  I or a member of my legal  staff have also  examined  and  relied  upon
originals or copies, certified or otherwise authenticated to my satisfaction, of
all corporate records, documents, agreements or other instruments of the Company
and have made all  investigations  of law and have  discussed with the Company's
representatives   all  questions  of  fact  that  I  have  deemed  necessary  or
appropriate.

      Based upon and subject to the foregoing, I am of the opinion that:

      1. The Company is a corporation  duly organized,  validly  existing and in
corporate good standing under the laws of the State of Delaware.

      2. The issuance and sale of the Shares as contemplated in the Registration
Statement have been duly authorized by the Company.
<PAGE>

      3. The Shares,  when issued and sold in accordance  with the provisions of
the Plan, will be validly issued, fully paid and nonassessable.


      I hereby  consent  to the filing of this  opinion  as  Exhibit  5.1 to the
Registration Statement.

                                          Very truly yours,


                                          /s/ Seth H. Hoogasian
                                          Seth H. Hoogasian
                                          General Counsel


<PAGE>




                                                                   Exhibit 23.1






            Consent of Independent Public Accountants
            -----------------------------------------


     As independent public  accountants,  we hereby consent to the incorporation
by  reference  in this  Registration  Statement  on Form S-8 of our report dated
February  16,  1999,  included  or  incorporated  by  reference  in  ThermoQuest
Corporation's Annual Report on Form 10-K for the year ended January 2, 1999, and
to all references to our Firm included in this Registration Statement.


                                             ARTHUR ANDERSEN LLP

Boston, Massachusetts
June 9, 1999
[{"type": "S-8", "sequence": "1", "description": "FORM S-8", "secsgml_size_bytes": 20229}]
{"company-data": {"conformed-name": "THERMOQUEST CORP \\DE\\", "cik": "0001005868", "assigned-sic": "3826", "irs-number": "770407461", "state-of-incorporation": "DE", "fiscal-year-end": "0102"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-80295", "film-number": "99643120"}, "business-address": {"street1": "2215 GRAND AVENUE PARKWAY", "city": "AUSTIN", "state": "TX", "zip": "787273812", "phone": "6176221000"}, "mail-address": {"street1": "81 WYMAN STREET", "street2": "P O BOX 9046", "city": "WALTHAM", "state": "MA", "zip": "02254-9046"}}
As filed with the Securities and Exchange Commission on June 9, 1999.
                              Registration No. 333-
-----------------------------------------------------------------

                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549
                                 ---------------

                                    FORM S-8
                             Registration Statement
                                      Under
                           The Securities Act of 1933
                                 ---------------

                             THERMOQUEST CORPORATION
             (Exact name of registrant as specified in its charter)
                                 ---------------

      DELAWARE                                             77-0407461
(State or other jurisdiction of                       (I.R.S. Employer
 incorporation or organization)                 Identification Number)

                            2215 Grand Avenue Parkway
                            Austin, Texas 78728-3812
               (Address of Principal Executive Offices) (Zip Code)

             THERMOQUEST CORPORATION EMPLOYEES EQUITY INCENTIVE PLAN

                            (Full Title of the Plan)

                          Sandra L. Lambert, Secretary
                           Thermo Electron Corporation
                                 81 Wyman Street
                                 P. O. Box 9046
                        Waltham, Massachusetts 02454-9046
                     (Name and Address of Agent for Service)

                                  (781) 622-1000
          (Telephone Number, Including Area Code, of Agent For Service)

                                   Copies to:
                    Seth H. Hoogasian, Esq., General Counsel
                           Thermo Electron Corporation
                                 81 Wyman Street
                                 P. O. Box 9046
                        Waltham, Massachusetts 02454-9046

                                 ---------------
CALCULATION OF REGISTRATION FEE

 TITLE OF                                         PROPOSED
SECURITIES         AMOUNT       PROPOSED          MAXIMUM            AMOUNT OF
  TO BE             TO BE       MAXIMUM           AGGREGATE        REGISTRATION
REGISTERED        REGISTERED    OFFERING        OFFERING PRICE          FEE
                                PRICE PER
                                  SHARE
  Common Stock,
 $.01 par value      500,000      $11.65625     $5,828,125(2)         $1,621
    per share       shares (1)       (2)

      In  addition,  pursuant to Rule 416(c) under the  Securities  Act of 1933,
this Registration Statement also covers an indeterminate number of shares of the
Company's  Common  Stock  issuable  in  connection  with  adjustments  under the
ThermoQuest  Corporation  Employees  Equity  Incentive  Plan to reflect  certain
changes in the Company's capital structure, including stock dividends or stock
splits.

(1)   Represents  additional  shares  available for grants under the ThermoQuest
      Corporation Employees Equity Incentive Plan as of June 9, 1999.

(2)   Estimated  solely  for  the  purpose  of  calculating  the  amount  of the
      registration  fee in accordance  with Rule 457(h) under the Securities Act
      of 1933.  The  Company  based  its  calculation  of the  proposed  maximum
      aggregate offering price on (1) the registration  herein of 500,000 shares
      of Common  Stock  and (2) the  average  of the high and low sales  prices,
      $11.6875 and $11.625,  respectively,  of the Company's Common Stock on the
      American  Stock  Exchange on June 8, 1999 as reported in the  consolidated
      reporting system.
EXPLANATORY NOTE

      This Registration Statement is being filed pursuant to General Instruction
E of Form S-8 in order to register  additional  securities  of the same class as
other  securities  for  which a  registration  statement  relating  to the  same
employee benefit plan is effective.

      This Registration Statement relates to 500,000 shares of the Common Stock,
$.01 par value per share,  of  ThermoQuest  Corporation  (the  "Company"  or the
"Registrant"),  that are reserved for issuance under the ThermoQuest Corporation
Employees Equity Incentive Plan (the "Plan").  On November 24, 1998, the Company
filed an initial  registration  statement on Form S-8 (Reg.  No.  333-67853)  to
register  1,000,000  shares of Common Stock reserved for issuance under the Plan
(along  with other plans of the  Company).  The  addition  of this  Registration
Statement  brings the total number of shares  registered  for issuance under the
Plan to 1,500,000.  The contents of the previously filed registration  statement
are  incorporated  herein by  reference  except for the items that are set forth
below.  Pursuant to Instruction  E, this  Registration  Statement  contains such
information  required by Form S-8 that is not otherwise included in the previous
registration statement.

                                     PART II

               INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  Incorporation of Documents by Reference.

      The Company is subject to the informational and reporting  requirements of
Sections 13(a),  13(c), 14 and 15(d) of the Securities  Exchange Act of 1934, as
amended (the "Exchange  Act"), and accordingly  files reports,  proxy statements
and other information with the Securities and Exchange Commission. The following
documents,  which  are on file with the  Commission,  are  incorporated  in this
Registration Statement by reference:

            (a)   The  Company's  Annual Report on Form 10-K for the fiscal year
                  ended January 2, 1999;

            (b)   The  Company's  Quarterly  Report on Form 10-Q for the quarter
                  ended April 3, 1999;

            (c)   The  description of the Common Stock which is contained in the
                  Company's  Registration  Statement on Form 8-A filed under the
                  Exchange Act, as amended from time to time.

      All reports or proxy statements filed by the Company under Sections 13(a),
13(c),  14 and 15(d) of the  Exchange  Act  after the date of this  Registration
Statement and before the filing of a post-effective  amendment  stating that all
securities  covered  by this  Registration  Statement  have been  sold,  or that
deregisters  all such securities  then remaining  unsold,  shall be deemed to be
incorporated by reference in this Registration Statement and to be a part hereof
from the respective dates of filing of such documents.
Item 5.  Interests of Named Experts and Counsel.

      The  validity of the Common Stock  offered  hereby has been passed upon by
Seth H.  Hoogasian,  Esq.,  General Counsel of the Company.  Mr.  Hoogasian is a
full-time  employee of Thermo  Electron  Corporation  ("Thermo  Electron"),  the
majority  stockholder of Thermo Instrument  Systems Inc. ("Thermo  Instrument"),
which in turn is the majority  stockholder of the Company,  is an officer of the
Company,  Thermo  Instrument and Thermo  Electron,  and owns or has the right to
acquire  6,000 shares of Common Stock,  18,815 shares of the common stock,  $.10
par value per  share,  of Thermo  Instrument  and  348,828  shares of the common
stock, $1.00 par value per share, of Thermo Electron.

Item 6.  Indemnification of Directors and Officers.

     The Delaware  General  Corporation  Law and the  Company's  Certificate  of
Incorporation  and By-Laws  limit the  monetary  liability  of  directors to the
Company and to its stockholders and provide for indemnification of the Company's
officers and directors for  liabilities and expenses that they may incur in such
capacities.  In general,  officers and directors are indemnified with respect to
actions  taken in good faith in a manner  reasonably  believed  to be in, or not
opposed to, the best  interests of the Company and, with respect to any criminal
action or proceeding,  actions that the  indemnitee  had no reasonable  cause to
believe were unlawful. The Company also has indemnification  agreements with its
directors and officers that provide for the maximum  indemnification  allowed by
law.

      The Company has an  insurance  policy  which  insures  its  directors  and
officers against certain  liabilities which might be incurred in connection with
the performance of their duties.

Item 8.  Exhibits.

      The Exhibit Index  immediately  preceding the exhibits is attached  hereto
and incorporated herein by reference.

Item 9.  Undertakings.

      (a)   The undersigned Registrant hereby undertakes:

            (1) To file,  during any  period in which  offers or sales are being
made, a post-effective amendment to this registration statement:

                  (i)    To include any prospectus required by Section
     10(a)(3) of the Securities Act of 1933;
(ii) To reflect in the  prospectus any facts or events arising
      after the effective date of the registration statement (or the most recent
      post-effective amendment thereof) which, individually or in the aggregate,
      represent  a  fundamental  change  in the  information  set  forth  in the
      registration  statement.  Notwithstanding  the foregoing,  any increase or
      decrease in volume of  securities  offered (if the total  dollar  value of
      securities  offered  would not exceed that which was  registered)  and any
      deviation from the low or high end of the estimated maximum offering range
      may be  reflected  in the form of  prospectus  filed  with the  Commission
      pursuant  to Rule 424(b) if, in the  aggregate,  the changes in volume and
      price  represent no more than 20 percent  change in the maximum  aggregate
      offering price set forth in the "Calculation of Registration Fee" table in
      the effective registration statement;

                  (iii) To include any material  information with respect to the
      plan  of  distribution  not  previously   disclosed  in  the  registration
      statement or any material change to such  information in the  registration
      statement.

      Provided,  however,  that paragraphs (a)(1)(i) and (a)(1)(ii) do not apply
if the  information  required to be included in a  post-effective  amendment  by
those paragraphs is contained in periodic reports filed with or furnished to the
Commission  by the  Registrant  pursuant  to Section 13 or Section  15(d) of the
Securities  Exchange  Act of 1934  that are  incorporated  by  reference  in the
registration statement.

            (2) That,  for the purpose of  determining  any liability  under the
Securities Act of 1933, each such post-effective amendment shall be deemed to be
a new registration statement relating to the securities offered therein, and the
offering of such  securities at that time shall be deemed to be the initial bona
fide offering thereof.

            (3)  To  remove  from  registration  by  means  of a  post-effective
amendment  any of the  securities  being  registered  which remain unsold at the
termination of the offering.

      (b) The undersigned  Registrant  hereby  undertakes  that, for purposes of
determining  any liability  under the Securities Act of 1933, each filing of the
Registrant's  annual report pursuant to Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 (and, where applicable,  each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of
1934) that is incorporated by reference in the  registration  statement shall be
deemed to be a new  registration  statement  relating to the securities  offered
therein,  and the offering of such securities at that time shall be deemed to be
the initial bona fide offering thereof.
(c)  Insofar  as  indemnification   for  liabilities   arising  under  the
Securities Act of 1933 may be permitted to directors,  officers and  controlling
persons of the Registrant  pursuant to the foregoing  provisions,  or otherwise,
the  Registrant  has been  advised  that in the  opinion of the  Securities  and
Exchange  Commission such  indemnification is against public policy as expressed
in the  Securities  Act and is,  therefore,  unenforceable.  In the event that a
claim for  indemnification  against such liabilities  (other than the payment by
the  Registrant  of  expenses  incurred  or  paid  by  a  director,  officer  or
controlling  person of the Registrant in the  successful  defense of any action,
suit or proceeding) is asserted by such director,  officer or controlling person
in connection with the securities being registered,  the Registrant will, unless
in the  opinion  of its  counsel  the matter  has been  settled  by  controlling
precedent,  submit to a court of appropriate  jurisdiction  the question whether
such  indemnification  by it is  against  public  policy  as  expressed  in  the
Securities Act and will be governed by the final adjudication of such issue.
SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the Registrant
certifies  that it has  reasonable  grounds to believe  that it meets all of the
requirements  for  filing  on Form S-8 and has  duly  caused  this  Registration
Statement  to be  signed  on its  behalf  by  the  undersigned,  thereunto  duly
authorized, in the City of Franklin,  Commonwealth of Massachusetts, on this 9th
day of June, 1999.

                                   THERMOQUEST CORPORATION

                                   By:  /s/ Richard W.K. Chapman
                                        Richard W.K. Chapman
                                        President and Chief Executive
                                        Officer

                                POWER OF ATTORNEY

      Each of the undersigned Directors and Officers of ThermoQuest  Corporation
hereby appoints Theo Melas-Kyriazi,  Paul F. Kelleher, Kenneth J. Apicerno, Seth
H.  Hoogasian  and  Sandra L.  Lambert,  and each of them,  his true and  lawful
attorneys-in-fact  and agents,  with full power of substitution,  for him and in
his  name,  place  and  stead,  in any and all  capacities,  to sign any and all
amendments (including post-effective amendments) to this Registration Statement,
and to file the same, with all exhibits thereto, and all documents in connection
therewith,  with the  Securities  and Exchange  Commission,  granting  unto said
attorneys-in-fact  and agents,  and each of them, full power and authority to do
and perform each and every act and thing  requisite  and necessary to be done in
and about the  premises,  as fully to all  intents  and  purposes as he might or
could  do  in  person,   hereby   ratifying   and   confirming   all  that  said
attorneys-in-fact  and  agents  or any of them,  or their or his  substitute  or
substitutes, may lawfully do or cause to be done by virtue thereof.

      Pursuant  to  the  requirements  of  the  Securities  Act  of  1933,  this
Registration  Statement  has been signed below by the  following  persons in the
capacities and on the dates indicated:

Signature                          Title                              Date

                                   President and Chief Executive
/s/ Richard W.K. Chapman           Officer                          June 9, 1999
-------------------------
Richard W.K. Chapman
/s/ Theo Melas-Kyriazi
-------------------------          Chief Financial Officer          June 9, 1999
Theo Melas-Kyriazi

/s/ Paul F. Kelleher               Chief Accounting Officer         June 9, 1999
-------------------------
Paul F. Kelleher

/s/ George N. Hatsopoulos          Director                         June 9, 1999
-------------------------
George N. Hatsopoulos

/s/ Frank Jungers                  Director                         June 9, 1999
-------------------------
Frank Jungers

                                   Chairman of the Board            June 9, 1999
/s/ Earl R. Lewis                  and Director
-------------------------
Earl R. Lewis

/s/ Anthony J. Pellegrino          Director                         June 9, 1999
-------------------------
Anthony J. Pellegrino

/s/ Michael E. Porter              Director                        June 9, 1999
---------------------
Michael E. Porter
EXHIBIT INDEX

Exhibit
Number            Description

5.1               Opinion of Seth H. Hoogasian, Esq.

23.1              Consent of Arthur Andersen LLP

23.2              Consent of Seth H. Hoogasian, Esq.
                  (contained in his opinion filed as
                  Exhibit 5.1).

24                Power of Attorney (see  signature  pages to this  Registration
                  Statement).
EXHIBIT 5.1

                             ThermoQuest Corporation
                            2215 Grand Avenue Parkway
                            Austin, Texas 78728-3812

                                                      June 9, 1999

ThermoQuest Corporation
2215 Grand Avenue Parkway
Austin, Texas 78728-3812

Re:   Registration Statement on Form S-8
      Relating to 500,000 Shares of the Common Stock,
      $.01 par value, of ThermoQuest Corporation

Dear Sirs:

      I am General Counsel to ThermoQuest  Corporation,  a Delaware  corporation
(the  "Company"),  and have acted as counsel in connection with the registration
under the  Securities  Act of 1933, as amended,  on Form S-8 (the  "Registration
Statement"), of 500,000 shares of the Company's Common Stock, $.01 par value per
share (the "Shares")  subject to the ThermoQuest  Corporation  Employees  Equity
Incentive Plan (the "Plan").

      I or a member of my legal staff have  reviewed the  corporate  proceedings
taken by the Company  with respect to the  authorization  of the issuance of the
Shares.  I or a member of my legal  staff have also  examined  and  relied  upon
originals or copies, certified or otherwise authenticated to my satisfaction, of
all corporate records, documents, agreements or other instruments of the Company
and have made all  investigations  of law and have  discussed with the Company's
representatives   all  questions  of  fact  that  I  have  deemed  necessary  or
appropriate.

      Based upon and subject to the foregoing, I am of the opinion that:

      1. The Company is a corporation  duly organized,  validly  existing and in
corporate good standing under the laws of the State of Delaware.

      2. The issuance and sale of the Shares as contemplated in the Registration
Statement have been duly authorized by the Company.
3. The Shares,  when issued and sold in accordance  with the provisions of
the Plan, will be validly issued, fully paid and nonassessable.

      I hereby  consent  to the filing of this  opinion  as  Exhibit  5.1 to the
Registration Statement.

                                          Very truly yours,

                                          /s/ Seth H. Hoogasian
                                          Seth H. Hoogasian
                                          General Counsel
Exhibit 23.1

            Consent of Independent Public Accountants
            -----------------------------------------

     As independent public  accountants,  we hereby consent to the incorporation
by  reference  in this  Registration  Statement  on Form S-8 of our report dated
February  16,  1999,  included  or  incorporated  by  reference  in  ThermoQuest
Corporation's Annual Report on Form 10-K for the year ended January 2, 1999, and
to all references to our Firm included in this Registration Statement.

                                             ARTHUR ANDERSEN LLP

Boston, Massachusetts
June 9, 1999