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To Show The Pressure Of The Atmosphere

Invert a tall glass or jar in a dish of water, and place a lighted

taper under it: as the taper consumes the air in the jar its pressure

becomes less on the water immediately under the jar; while the

pressure of the atmosphere on the water without the circle of the

jar remaining the same, part of the water in the dish will be forced

up into the jar, to supply the place of the air which the taper has

consumed. Nothing but the pressure of the atmosphere could thus cause

part of the water to rise within the jar, above its own level.