Fortin type mercurial barometer
Date: circa 1850
Inventory Number: DW0756
Classification: Barometer
Subject:
Maker: Adie & Son (1835 - 1880s)
User: Schlagintweit Brothers (1854 - 1858)
Dimensions:
100.5 x 5 cm (39 9/16 x 1 15/16 in.)
case: 8 x 104 x 8 cm (3 1/8 x 40 15/16 x 3 1/8 in.)
Accessories: pine case.
Description:
A mercurial barometer in a gun metal frame with a silvered scale (25-99cm) and two sliding verniers. It has a cylindrical metal canister with an adjusting screw at its bottom and rectangular window. A thermometer with a scale between -40 and 50 degrees Celsius is attached to it.
Signedon barometer: Adie London No. 36
Inscribedon side opposite scale: SCHLAGINTWEIT No. 4
on lid of pine case: oben Piano nicht stürzen
on lid of pine case: oben Piano nicht stürzen
FunctionA portable instrument for measuring atmospheric pressure. When used, it would be placed vertically (preferrably on a tripod) with the canister at the bottom. The height of the mercury in the canister would be adjusted first with the screw, and then the reading would be taken from the scale on the upper part of the barometer at the place of the mercury level. Great precision could be attained by the use of the verniers, which also serve to make sure the reading is being taken from a truly horizontal perspective.
Its thermometer is used to make corrections to the readings at temperatures different from the standard.
Its thermometer is used to make corrections to the readings at temperatures different from the standard.
Historical AttributesThis thermometer apparently went on the Schlagintweit expedition to India between 1854 and 1858.
Curatorial RemarksVery similar to DW0755 except for the carrying case and scales.