Mercury stick barometer
Title
Mercury stick barometer
Subject
Astronomy
Weather instrument
Barometer
Measuring instrument
Weather instrument
Barometer
Measuring instrument
Description
Wood, metal, glass, mercury
Housed in wooden box with glass sides, hinged wood/glass door, case is 9 ¼ x 6 ¼ x 50 ¾ inches. Originally kept in the entrance hall on the west wall, just north of the door to the transit rooms. Glass on front door broken.
Consists of mercury in a glass tube encased by chrome and brass tube. Provided with two scales read with a vernier to 0.002 of an inch and 0.05 mm. Range is 66 mm to 83 mm and 26 in to 32.5 in. Vernier moved by turning an attached wheel. Thermometer mounted on barometer measures temperature of the mercury in Centrigrade. Barometer is 45 inches long. Suspended to Mahogany board by a hanger at the top with steadying screws at the bottom cistern. White opal glass plates attached to board for reading the instruments. Inscribed on cistern with “Henry J. Green, New York,” the number 3603 on thermometer and number 3138 on the mercury scale.
The barometric pressure and the temperature were two important factors in determining the atmosphere’s index of refraction. The index of refraction was necessary for transit observations.
Housed in wooden box with glass sides, hinged wood/glass door, case is 9 ¼ x 6 ¼ x 50 ¾ inches. Originally kept in the entrance hall on the west wall, just north of the door to the transit rooms. Glass on front door broken.
Consists of mercury in a glass tube encased by chrome and brass tube. Provided with two scales read with a vernier to 0.002 of an inch and 0.05 mm. Range is 66 mm to 83 mm and 26 in to 32.5 in. Vernier moved by turning an attached wheel. Thermometer mounted on barometer measures temperature of the mercury in Centrigrade. Barometer is 45 inches long. Suspended to Mahogany board by a hanger at the top with steadying screws at the bottom cistern. White opal glass plates attached to board for reading the instruments. Inscribed on cistern with “Henry J. Green, New York,” the number 3603 on thermometer and number 3138 on the mercury scale.
The barometric pressure and the temperature were two important factors in determining the atmosphere’s index of refraction. The index of refraction was necessary for transit observations.
Creator
Henry J. Green & Company, New York
Publisher
Astronomy Department, University of Illinois, Urbana, Illinois
Date
1896
Contributor
Michael Svec
Rights
Copyright Michael Svec
Format
image/jpg
Language
English
Type
physical object
Identifier
University of Illinois Observatory Collection A129
University ID 016673, obs79
University ID 016673, obs79
Coverage
University of Illinois Observatory, Urbana, Illinois
Files
Collection
Citation
Henry J. Green & Company, New York, “Mercury stick barometer,” University of Illinois Observatory Collection, accessed April 26, 2024, https://uiobservatory.omeka.net/items/show/15.