AEROSTATICS.

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AEROSTATICS.

Sect. I.

OF HEAT.

In treating of Aeriform Fluids, we begin with theconsideration of Heat , which, though it affect allmaterial substances, acts more remarkably on elas-tic fluids than on other bodies. We shall treat ofheat as affecting the Bulk, the Fluidity, and theElasticity of bodies.

308 . Heat or caloric may be regarded as asubstance that penetrates and expands all bodies,and that produces in us the sensations of heatand cold.

Though we conceive heat to be a substance, it is neverfound in an independent state, or existing otherwisethan as a property of body.

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309. A*