recording barometer
Date: late 19th-mid 20th Century
Inventory Number: 1998-1-0851
Classification: Barometer
Subject:
Maker: James J. Hicks (fl. 1874 - 1952)
Cultural Region:
Place of Origin:
City of Use:
Dimensions:
19.2 × 40 × 24.6 cm (7 9/16 × 15 3/4 × 9 11/16 in.)
Description:
Aneroid barograph, resting on a rectangular wooden platform with moulding and a raised central portion, and covered with a glass rectangular cover with wooden framing. There is a smaller rectangular setion of metal screwed into the raised central portion, where the other parts of the instrument stand.
Seven small, circular aneroid capsules are stacked in series, and connected via levers to a metal arm. The metal arm ends in a pen tip and is placed so that it can inscribe a line onto a paper graph with columns corresponding to the days of the week, and a barometric scale in inches. This graph is wrapped around a metal drum with a metal knob on top and a screw to the side of the top disc.
An open metal cylinder towards the back of the instrument holds a small glass bottle with a glass stopper, which probably would have once held ink for the instrument, but it is now empty.
Seven small, circular aneroid capsules are stacked in series, and connected via levers to a metal arm. The metal arm ends in a pen tip and is placed so that it can inscribe a line onto a paper graph with columns corresponding to the days of the week, and a barometric scale in inches. This graph is wrapped around a metal drum with a metal knob on top and a screw to the side of the top disc.
An open metal cylinder towards the back of the instrument holds a small glass bottle with a glass stopper, which probably would have once held ink for the instrument, but it is now empty.
Signedabel on base (ivory?): J.J. HICKS / LONDON ENG
Inscribedon paper graph: Stormograph
FunctionBarographs such as this use the partially evacuated metal capsule of aneroid barometers, which are very sensitive to pressure changes, and contract or expand in accordance with outside air pressure. Because the movement of a single aneroid capsule is extremely small, often there are many stacked in series to amplify the change. In this case, there are seven. These capsules are linked by a series of gears or levers to a metal arm with a scribe or pen tip so that the vertical position of the pen corresponds with the atmospheric pressure as read by the capsules. The pen then draws a continuous record of atmospheric pressure onto a chart of paper or smoked foil, mounted on to a drum which is rotated by internal clockwork. This instrument provides one week's wort of recordings per revolution of the drum.
Because atmospheric pressure also corresponds to changes in altitude, barographs can also be used to track elevation.
Because atmospheric pressure also corresponds to changes in altitude, barographs can also be used to track elevation.
ProvenanceUsed by the A.T. Kinney Steamshop Co. Given to the Collection by a relative of Albert T. Kinney in 1982.