air pump
Datecirca 1855
Inventory Number1996-1-0458
ClassificationAir Pump
Subject
Maker
Edward Samuel Ritchie
1814 - 1895
Cultural Region
Place of Origin
Dimensions70.5 × 82.5 × 35 cm (27 3/4 × 32 1/2 × 13 3/4 in.)
Material
Bibliography
DescriptionThe air pump consists of a single barrel on top of which a long rod connects the piston to the lever. The latter is supported by a turned column. There is also a small mercury cup (to prevent air leakage) and a thumb screw. Once the latter has been removed, a barometer and siphon gauge could be added to the pump (missing here). The lever is decorated in colors with flower motifs. The barrel is connected to a brass tube to the vacuum plate. A stopcock controls the flow of air to the plate. On top of the plate, covered in glass, there is a nozzle that would have been connected to another apparatus. On top of the vacuum plate would have been set a glass bell jar. The whole apparatus is supported by a wooden board (either mahogany or rosewood) on four turned feet.
Signedon top of barrel: E. S. RITCHIE / BOSTON
FunctionAn air-pump is an instrument used to produce a vacuum in order to study nature under controlled environmental conditions. It became one of the most important scientific instruments of natural philosophy as early as the late seventeenth century. With the electrostatic machine, the air-pump became in time not only a genuine research tool but an important pedagogical apparatus in the lecturer-demonstrator's arsenal. Ritchie, as most instrument makers, sold several kinds of these, ranging in price from $10 to $300.
In this model, a glass bell jar would have been put on the plate. The experiments would have taken place inside the bell jar.
This is how Ritchie introduced his air pumps in 1855: "As so many experiments depend on the perfection of this instrument, I have spared no expense in my machinery for making every part in the most perfect manner. I have introduced some improvements in its construction. My pumps are made on the principle of Leslie, but much improved."
In this model, a glass bell jar would have been put on the plate. The experiments would have taken place inside the bell jar.
This is how Ritchie introduced his air pumps in 1855: "As so many experiments depend on the perfection of this instrument, I have spared no expense in my machinery for making every part in the most perfect manner. I have introduced some improvements in its construction. My pumps are made on the principle of Leslie, but much improved."
Accum & Garden
Date: 1850-1854
Accessories: glass vessel with stopcock
Object number: 1996-1-0353
Rudolph Koenig
Date: 1865-1890
Object number: 1997-1-0919