Accession No
2705
Brief Description
Hutchinson’s surveying aneroid barometer - altimeter, by Elliott Brothers, English, c. 1890
Origin
England; London; 101 and 102 St. Martins Lane WC
Maker
Elliott Brothers
Class
meteorology; surveying
Earliest Date
1873
Latest Date
1900
Inscription Date
Material
metal (gilt brass, steel); glass
Dimensions
length 71mm; breadth 51mm; thickness 20mm
Special Collection
Provenance
Purchased from Christie’s, South Kensington, London, England; lot 96, 8/1/1981.
Inscription
‘Hutchinsons Improved Surveying Aneroid
Compensated
Keep the eye level with the needle
On ascending point of needle goes up
On descending it goes down
Elliot Bros.
101 & 102 St. Martins Lane
LONDON W.C.
2985.’
‘RAIN FAIR’
‘H.P.’ (on reverse)
Description Notes
Hutchinson’s surveying aneroid barometer / altimeter, by Elliott Bros., 1890 (c).
Vidie capsule. Hutchinson’s improved surveying aneroid. Gilt brass case; glazed cover; blued steel needle; face graduated, pressure 25-31 inches. Rotating outer dial graduated, altitude +1000 feet - 0 - -1000 feet; lug handle.
References
Events
Description
A barometer measures the pressure of the air around us. The precise pressure of the air depends upon the weather, so a barometer is useful for weather forecasting. It can also be used as an altimeter (see "how to use" a hypsometer).
This is an aneroid barometer adapted by Major Hutchinson in about 1870 for military surveys. In addition to the normal barometer scale of 26 to 31 inches there is is a subsidiary scale, ranging from + 1000 feet to - 1000 feet, which can be rotated via the knurled bezel ring so that its zero can be set against the instrument pointer. The user is instructed to hold the pointer at eye level, to avoid errors of parallax. From then on, as the user moves about his territory, the pointer can be read against the subsidiary scale to show his changes in altitude. It avoids the need for noting the starting and finishing altitudes, although it gives no indication of the actual altitude.
26/03/2008
Created by: Dr. Anita McConnell on 26/03/2008
FM:44534
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