This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1850 Excerpt: ...one half the original quantity. If we had taken a smaller receiver, the rate of exhaustion would have been much more rapid. Thus, if the receiver had only the capacity of the barrel, the series would have been, j, T'T, 55, ?V- Ttt- S7' Ttt Tt'tt 5 so that, with ten strokes of the piston, the air of the receiver would ...
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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1850 Excerpt: ...one half the original quantity. If we had taken a smaller receiver, the rate of exhaustion would have been much more rapid. Thus, if the receiver had only the capacity of the barrel, the series would have been, j, T'T, 55, ?V- Ttt- S7' Ttt Tt'tt 5 so that, with ten strokes of the piston, the air of the receiver would have been rarefied more than one thousand times. As this series never terminates, it is evident that a complete exhaustion can never be effected by the air-pump. Indeed, in practice, the vacuum is far less perfect than the theory would make it by the repetition of the blows of the piston; for when the air in the receiver becomes very much rarefied, it has not elasticity sufficient to raise the valve at the bottom of the barrel; or even if that difficulty is obviated by a different construction of the valve, still the difficulty of making the joints and valves perfectly air-tight, is such as to impair the perfection of the void. In the most improved air-pumps, the valves are made of small pieces of metal, which are opened and closed by the action of the piston itself. Also to prevent the corrosion of brass, arising from the action of the oil employed to lubricate the parts, in the place of this material, glass is now used for the barrels and the plate of the pump, and the piston is made of steel. 457. By means of this instrument, we may obtain very striking illustrations of the mechanical properties of air. (1.) The pressure of the air acts with great force on all bodies at the surface of the earth, amounting, as we shall show hereafter, to nearly 15 pounds upon every square inch, or more than 2000 pounds upon a square foot. Upon so large a surface, therefore, as that of the human body, the pressure amounts to no less tha...
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Add this copy of An Introduction to Natural Philosophy Designed as a to cart. $32.88, new condition, Sold by Paperbackshop rated 4.0 out of 5 stars, ships from Bensenville, IL, UNITED STATES, published 2013 by Hardpress Publishing.
