Air pump and condenser, 1761
This air pump by George Adams is the centrepiece of the pneumatics apparatus commissioned by George III in 1761. The arrangement of valves is copied from a pump made about 10 years earlier by John Smeaton, who later became famous as a civil engineer. The air pump can be used to remove air from a container, such as the glass jar shown, to show the effects of air pressure, for example. Alternatively, it can be used to pump air into a container to show the effects of pressure higher than normal.
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