Davis Hygrometer

<< >>
The 1901 Factory and Works Act established precise limits as to the amount of water vapor that would be allowed in British industrial settings. These limits were especially important in coal mines where some water could lessen the chance of explosions, but too much water could lead to medical problems for the miners.
This hygrometer was made to measure humidity in mines, and may have been used in West Virginia. The inscription reads: "John Davis & Son (Derby) Ltd. No. 443 Derby & London. Reg No. 518758." This was an English firm that specialized in mathematical and other instruments for the mining industry. Comes with a case.
Ref.: Henry Davis, "The Application of the Hygrometer in Coal Mines," Transactions of the Institute of Mining Engineers 35 (1907-1908): 285-290.
Currently not on view
date made
ca 1925-1950
Davis Derby Ltd.
place made
United Kingdom: England, Derby
overall: 9 in; 22.86 cm
overall in case: 9 1/2 in x 3 in x 3 3/8 in; 24.13 cm x 7.62 cm x 8.5725 cm
ID Number
catalog number
accession number
See more items in
Medicine and Science: Physical Sciences
Measuring & Mapping
Natural Resources
Thermometers and Hygrometers
Data Source
National Museum of American History


Add a comment about this object