Mason's Hygrometer


This instrument consists of wet and dry bulb thermometers with a liquid vial (missing in this instance) in between, mounted on a wooden board. The inscriptions on the board read "MASON'S HYGROMETER" and "B. PIKE JR. 294 BROADWAY, NEW YORK." The scales for the thermometers are on the board. That for the dry-bulb thermometer is graduated every degree Fahrenheit from 0 to +135. That for the wet-bulb thermometer is graduated every degree Fahrenheit from -5 to +145.

John Abraham Mason, an English surgeon, described the form in 1836. Benjamin Pike Jr., a leading purveyor of instruments in New York between 1843 and 1864, claimed that the use of an instrument of this sort "in the sick chamber will be at once evident, as a fire kept up in a closed room naturally dries the air which the patient has to breathe."

Ref: John Abraham Mason, "Description of a New Hygrometer," Records of General Science 4 (1836): 23-35 and 96-111.

B. Pike Jr., Illustrated, Descriptive Catalogue of Optical, Mathematical and Philosophical Instruments (New York, 1856), vol. 2, pp. 135-138.

Date Made: 1843-1864

Maker: B. Pike, Jr.

Location: Currently not on view

Place Made: United States: New York, New York City

See more items in: Medicine and Science: Physical Sciences, Thermometers and Hygrometers, Measuring & Mapping


Exhibition Location:

Credit Line: John William Christopher Draper and James Christopher Draper

Data Source: National Museum of American History

Id Number: PH.333982Accession Number: 304826Catalog Number: 333982

Object Name: Mason's hygrometerhygrometer

Measurements: overall: 8 13/16 in x 2 7/16 in x 1 1/8 in; 22.38375 cm x 6.19125 cm x 2.8575 cm


Record Id: nmah_1289953

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