Hicks Solar Radiation Thermometer

In the late 18th century, scientists set out to determine the intensity of solar radiation overall, as well as the intensity of radiation in different parts of the spectrum. In time they learned that the temperature of a black object was related to the intensity of the incident radiation and the movement of the ambient air. Negretti & Zambra’s solar radiation thermometer, the first commercial instrument suitable for this purpose, was unveiled in 1864. It had a blackened bulb, and was encased in a second glass tube from which the air had been evaporated. James J. Hicks obtained a British patent for a method of testing the vacuum of a solar thermometer in 1873, and described his solar radiation thermometer at a meeting of the British Meteorological Society in early 1874.
This example consists of a mercury-in-glass thermometer with a constriction in the stem just above the spherical bulb. The white enamel back of the stem is marked "202" and "J. Hicks. 8 Hatton Garn. London" and "Hicks's Patent No. 3647" and "14951" with the K/O monogram of the Kew Observatory. The clear front is graduated every degree F. from -5 to +192. This thermometer is encased in a glass jacket from which the air has been evacuated. The jacked is provided with two platinum electrodes that can be connected to a spark coil so that the vacuum can be checked, a feature described in Hicks' 1873 patent. It was made after the issuance of Hicks' patent in 1873 and before the expansion of his business to 8, 9, & 10 Hatton Garden in the 1880s.
Ref.: W. E. K. Middleton, A History of the Thermometer (Baltimore, 1966), pp. 162-164.
James J. Hicks, Illustrated and Descriptive Catalogue of Standard, Self-Recording, and Other Meteorological Instruments (London, n.d.), pp. 60-61.
Currently not on view
Object Name
solar radiation thermometer
date made
ca 1873-1885
J. J. Hicks
thermometer: 13 1/2 in; 34.29 cm
jacket: 16 in; 40.64 cm
place made
United Kingdom: England, London
ID Number
accession number
catalog number
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, Kenneth E. Behring Center


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