Pneumatics.

^ Pressure, is by raising the Mercury, byExpansion of a small Quantity of con-sted Air, to the same Height in an ex-isted Tube above the Pump, as thatj^sich it i s ra if e d to in the Mercurial Gagev the Pressure of the Atmosphere be-S it.

The great Action of animal Life, viz.gashing by Inspiration and Expiration of^' r > is owing to the Pres'ure and Spring ofAir conjointly, as is evident by the° nt raSiion and Expanson of a Bladder in a^ a ” Receiver, with a Bladder tied on at^tom to represent the Diaphragm.

Hence the Necessity of Air for Respira-**° n and animal Life in most Sorts of Crea-ks, which die very soon in the exhaufledReiver; Though some Animals will notJ; killed in this manner ; as Flies, Frogs ,some sort of Fishes, &c.

^ Th At ^ir passing through the Fire, and^ e ated Brass Tube, is unfit for animalP'raticm, is shewn by the sudden Deatht , ail y Animal put into a Receiver filledere With. Also Candles and living Coals,QU immediately go.

0 * Hence the noxious and pestilential^S a Hties of Damps and suffocating Exhala~frequent and fatally experienced inlries » and other subterranean Places.

That

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