Exhibit 12(a)(13)


Investor Contact: 781-622-1111
Media Contact: 781-622-1252

       THERMO INSTRUMENT COMPLETES CASH TENDER OFFER FOR METRIKA SYSTEMS

WALTHAM, Mass., April 28, 2000 - Thermo Instrument Systems Inc. (ASE-THI), a
Thermo Electron company, announced today that it has successfully completed
the cash tender offer of $9.00 per share for any and all outstanding shares
of its Metrika Systems Corporation subsidiary.

     The offer and withdrawal rights expired at midnight on Thursday,
April 27, 2000. Based on the preliminary report of the depositary for the
offer, American Stock Transfer & Trust Company, approximately 1.2 million
Metrika Systems shares were tendered. This brings Thermo Instrument's and
Thermo Electron's combined equity ownership in Metrika Systems to
approximately 94.6 percent. Thermo Instrument expects to complete the spin-in
of Metrika Systems by Wednesday, May 3, through a short-form merger. The
short-form merger does not require Metrika Systems' board or shareholder
approval.

     Metrika Systems shareholders who tendered their shares in the tender
offer will receive payment for their shares shortly. Metrika Systems
shareholders who did not tender their shares will also receive $9.00 per
share in the short-form merger. Information outlining what steps these
shareholders must take to obtain payment will be mailed within a week to 10
days.

     Thermo Instrument Systems Inc. is a global technology company serving
multiple markets, including the life sciences, telecommunications, food and
beverage, chemical, and oil and gas industries, with instrumentation,
information-management software, and worldwide service for a range of
applications. Our products help scientists make the discoveries that will
fight disease and prolong life. They increase the speed and quality of
communications. And they provide knowledge about the quality of materials
used in manufacturing, improve the manufacturing process, and protect the
environment. More information is available on the Internet at
http://www.thermo.com/subsid/thi1.html.

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