H. J. Green Maximum Thermometer

This mercury-in-glass thermometer is designed so that an air bubble separates a small bit of mercury from the main part of the column. When the temperature falls, the detached mercury remains in place indicating the maximum temperature attained, until reset by the observer. John Phillips, an English geologist, introduced the form at the 1832 meeting of the British Association for the Advancement of Science. In 1856 he showed an improved form made by Louis P. Casella of London.
Appleton's Encyclopaedia noted in 1860 that James Green of New York "appears to have removed the objections to the previous forms of the maximum thermometers, and produced a highly simple and perfect instrument." Henry J. Green, who was James Green's nephew and successor, also made instruments of this sort. This example has a grooved aluminum plate that is marked "H. J. GREEN B'KLYN. N.Y." and "No. 12701 U.S. WEATHER BUREAU" and "MAXIMUM" and is graduated every 5 degrees Centigrade [?] from -25 to +55 degrees. The bulb is spherical. The stem is marked "U.S. 12701" and graduated every degree from -29 to +57.
Ref.: Henry J. Green, Meteorological and Scientific Instruments (Brooklyn, 1900), p. 22.
Currently not on view
Object Name
maximum thermometer
date made
after 1890
H. J. Green
plate: 12 in; 30.48 cm
tube: 10 in; 25.4 cm
place made
United States: New York, Brooklyn
ID Number
accession number
catalog number
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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