Tonnelot Thermometer

<< >>
This mercury-in-glass thermometer has a cylindrical bulb. The tube is marked, in red, “Tonnelot à Paris (1884.5) 4289” and graduated from -10.2 to 108.0 degrees (Centigrade?). It is probably one of the very precise thermometers with a tube of extra-hard glass that was made by Tonnelot for the International Committee of Weights and Measures, tested at the Bureau International at Sèvres, and distributed to government organizations around the world. It came to the Smithsonian from the U.S. Weather Bureau.
Ref: J. A. Hall, “The International Temperature Scale Between 0 Degrees and 100 Degrees C,” Philosophical Transactions 229 (1930): 1-48.
Currently not on view
date made
ca 1884
Tonnelot, Jules
place made
France: Île-de-France, Paris
overall: 25 1/2 in; 64.77 cm
overall: 25 5/8 in x 1/4 in; 65.0875 cm x .635 cm
ID Number
catalog number
accession number
Credit Line
U.S. Weather Bureau
See more items in
Medicine and Science: Physical Sciences
Measuring & Mapping
Thermometers and Hygrometers
Data Source
National Museum of American History


Add a comment about this object