The Thermodad

Every so often, the WCMA receives an interesting artifact that requires extra research to fully understand its function. We invite you to join our curatorial staff as they investigate our newest mystery object!

Where do we begin?

  • Whenever we receive a new artifact we answer a few basic questions:
  • What is it?
  • Where and when was it made?
  • Who made it? Who used it?
  • How was it used?
  • What is its connection to Wellington County?

If we discover that an artifact was manufactured in Wellington County, we ask more questions to learn more about the company that made it: When was it founded and who owned it? Where was it located? How many people worked there? What else did they make? Every answer leads to more questions, but that's half the fun!

photograph Thermodad 
Caption: The Thermodad
Credit: WCMA, 2015.15.29.01.

Where do we look for answers?

Our first line of inquiry is to speak with the donor of the object. Often they can provide us with some clues to guide us in our research. In the case of our mystery object, the donor did not have any additional information to provide.

Next, we turn to the artifact itself. We examine it for manufacturer's marks and patent dates and looks for clues as to its function. At first glance, it seems to be a type of hot water bottle or bed warmer. It is made of metal, with a screw-on cap and it is empty. The body is circular and flat, measuring eight inches in diameter and is one inch thick. It has no markings on any of its surfaces.

We also examine materials that came with the artifact, such as packaging and documents. Fortunately, the mystery object came with two paper advertisements that answer some of our initial questions. From these documents we learn that this object is called a Thermodad. Our initial observations were partially correct: the Thermodad was used for the same purpose as a hot water bottle, but it functions very differently. Instead of requiring hot water to provide heat, the Thermodad was originally filled with a chemical that would react with air to provide heat through a chemical reaction.

photograph of ad


Caption: According to the advertisements, the Thermodad was manufactured exclusively by Hercules Metals Limited of Elora, Ontario. Consumers could purchase one of these products directly from the manufacturer by mail order for $3.49.

Credit: WCMA, 2015.15.29.02

What information are we missing?

  • Where in Elora was Hercules Metals Limited located?
  • How long did it operate?
  • Who owned it?
  • What else did they make?
  • When did they produce the Thermodad, and how many did they make?
  • Did they register any trademarks or patents related to this product?

To answer these questions, we turn to a variety of sources. First, we check our artifact and archival collection to see if we have any related material. This could be in the form of other artifacts manufactured by Hercules Metal Limited, documents related to the company, a business directory or map for Elora or Wellington County, correspondence that mentions the business, or even photographs that might reveal its location.

We also comb through local history resources such as the Women's Institute Tweedsmuir Histories, Wellington County Historical Society Essay and Journal Collection, and Wellington County Local History Articles. These are digitized and searchable on our website and we consult them often. We can also consult the newspaper collection held by our Archives that contains local newspapers from 1852 to the present. These publications might include additional advertisements or news articles that mention either the Thermodad or Hercules Metals.

Thanks to the Internet, checking other sources for information has become a lot easier than in the past. The Government of Canada has made trademark, patent, copyright and industrial design information available online. These databases are often invaluable in our research, but unfortunately they have not been helpful yet in this case. The search continues!

How can you help?

Our own research efforts are ongoing, but help is always welcome. If you recognize the Thermodad or recall anything about Hercules Metals Limited, our staff would love to hear from you!

Email Hailey Johnston, Curator

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