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Exceptional Moto-Meter Collection At The AACA Library

The AACA Library & Research Center in Hershey, PA, has announced a year-long exhibit of the Francis G. Clax Collection of radiator-mounted temperature gauges in its lobby. Contained in the public display is a treasure trove of the temperature gauges and information about them.

More commonly referred to as the Motometer, that name only applies to the Boyce Moto-Meter that was invented by Harrison Hurlbert Boyce. He filed the first patent for his gauge on October 18th, 1912 that was granted on March 13th, 1913. The unit was designed for mounting on a radiator cap with a hole drilled through its center. Contrary to popular belief, it does not measure coolant temperature, but instead that of the air just above it in the radiator.

Boyce Moto-Meter

  •   The oldest known surviving 1914 Boyce Standard Moto-Meter from the Francis G. Clax Collection.

The Boyce Moto-Meter made its public debut at the 1912 New York Auto Show. Soon the Stewart-Warner Speedometer Co. and over a dozen other firms around the world would follow suit and design and manufacture similar devices. Millions of the temperature gauges in many different styles would be produced up until the pre-World War II years.

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  •            L to R: Heat-Ometer – Auto-Con-Den-So Meter – Anco Chief Mototector – Arrowmeter.

The Clax Motometer Collection containing many of these devices will be on display at the AACA Library & Research Center at the Club Headquarters located at 501 West Governor Road, Hershey, PA. for the next year. The facility is open daily during normal business hours, and you will also be able to see the exhibit next fall during the AACA Hershey Meet. You can learn more about the Library at the AACA Library & Research Center here.


  •             “The Automobile” June 4th 1914  ad showing a Moto-Meter win and use at Indianapolis.

Boyce Moto-Meter

  •                         1921 Boyce Moto-Meter advertisement showing a motorist and his chauffeur.

In the display are many early automobile radiator-mounted engine temperature indicating gauges, including the oldest known surviving unit. The exhibit also includes other unique and rare related items, such as original company documents, catalogs, and manuals. You can learn more about the subject at Francis Clax’s excellent website Motometer Central and here at The Old Motor. All photos are courtesy of the AACA Library and Motometer Central.

  •       The Francis A. Clax Motometer Collection on display with an early Mitchell at the AACA Library.

Francis A. Clax Motometer Collection on display with an early Mitchell at the AACA Library


7 responses to “Exceptional Moto-Meter Collection At The AACA Library

  1. The Boyce factory building in Long Island City still stands in good shape. It took several years for me to track it down, as the address listed when Boyce was in business had its name changed to a numbered street address from its original name when all the streets were reassigned numbers rather then word names decades ago. It is within a short distance from the 59th Street (Queensboro) Bridge .

  2. I wonder if Motometer ever manufactured their product or if was always done by Taylor Instruments? Taylor Instruments is still around today, manufacturing thermometers and other instruments for home and professional use.

    • Hi Jim C,

      Yes, the Motometer Co. did manufacture their Boyce Moto-Meter engine heat/temperature indicator. In early 1917, the Motometer Co. had the wherewithal, (money, facilities, skilled workforce, and customers) to begin assembly at their newly acquired factory located at 15 Wilbur Avenue Long Island City, New York thanks to a sizeable investment from George H. Townsend II Yale University roommate and highly successful attorney, Paul Lansing Veeder.

      From 1914 to mid-1916 the Motometer Co. relied upon skilled thermometer instrument manufacturer, Taylor Instrument Company, to make their thermometers and assemble all of the other Boyce Moto-Meter components. Some 6,000 of these early Boyce Moto-Meters were manufactured in total. They are based upon Harrison’s fundamental indicator patent and are specifically designated by the “Made By Taylor Instrument Companies” engraving on the glass crystal retaining bezels and unique temperature indicating scale dial plate, among other distinguishing features.

      By the 1920s the Motometer Co. was operating three factories around the clock in effort to keep pace with customer demand. Many women performed the manufacture and in-house precision assembly function. In June 1926, the company had sold some eight million units. And, within a month that number increased by two million.

      The Taylor and Motometer Co assembly agreement fell apart due to the pay upon receipt requirement and no Net payment agreement terms. As well, Taylor restricted thermometer sales to all non-U.S. government military customers in support of the WWI effort and government contract. By 1916 Harrison Boyce tired of the unfavorable payment terms and had pushed Townsend to find the means to bring as much of the manufacture and assembly process in-house as possible. Enter Paul Veeder.

      Boyce Moto-Meter case housing (or frames) were always sand cast by the Doehler Die Casting Company of nearby Newark, New Jersey and remained the key supplier throughout the lifecycle of the radiator-mounted product.

      The glass crystals were supplied by Corning.

      Thanks, David, for the opportunity to respond in benefit of your site subscriber.

  3. I have a vintage radiator cap with the presidential seal of the United States of America on it. Need help with the to ID this winged radiator cap

  4. i have a motor meter called guardene made by the pyrene mfg co in newark nj i can not find any information on it can you help me with it ronald r phillips

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