Dewpoint Hygrometer

University College

Accession Number: 2009.uc.19

Description:

Rectangular black box mounted vertically on a black metal column; copper tubes on either side with nozzles and stopcocks that feed into the flat top; a third copper tube leads up to a small cup; glass windows opposite each other on body; brass post mounted behind apparatus with ring clamp reaching above top of body; circular brass base.

Alternative Name:

Primary Materials: metal, copper, glass, brass

Markings:

Old Inventory Number = “uc19”. Base labeled “no. 65 L. Golaz Constr. 24 rue des Fosses St. Jacques, Paris 1880”.

Dimensions (cm): Height = 24.5 , Base diameter = 10

Function:

Used for the precise determination of relative humidity.

Condition:

Associated Instruments:

Manufacturer: L. Golaz, Paris

Date of Manufacture: 1880

Provenance: Part of University College Collection.

Historical Notes:

Invented by Alluard in 1877. A similar instrument is found in the Humboldt State University Collection (see Links). Also see W.E. Knowles Middleton (1969). Invention of the Meteorological Instruments.