Negretti & Zambra Thermometer, Absolute Scale

This is a sensitive precision instrument that was probably used as a standard for evaluating instruments sent to meteorological field stations. The mercury-in-glass thermometer is mounted on a white porcelain plate marked "NEGRETTI & ZAMBRA, SCIENTIFIC INSTRUMENT MAKERS, LONDON" and "ABSOLUTE" and "29" with the M/O monogram of the British Meteorological Office, the N/Z monogram of the firm, and the K/O monogram of the Kew Observatory.
The plate is graduated every 5 degrees from 245 to 325. The back of the stem is white enamel and marked "29" and with the M/O and N/Z monograms; the front is graduated every degree from +243 to +325 and numbered at 245, 273, and 320. It came to the Smithsonian from the U.S. Weather Bureau.
Currently not on view
Object Name
absolute thermometer
date made
early 20th century
Negretti & Zambra
overall: 11 in; 27.94 cm
place made
United Kingdom: England, London
ID Number
accession number
catalog number
Measuring & Mapping
U.S. Weather Bureau
Thermometers and Hygrometers
See more items in
Medicine and Science: Physical Sciences
Thermometers and Hygrometers
Data Source
National Museum of American History, Kenneth E. Behring Center
Credit Line
U.S. Weather Bureau

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