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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. 1854 Excerpt:...laborious experiments of M. V. Regnault show that it is not correct, it is, nevertheless, likely to maintain its position among practical men, on account of its simplicity and sufficient accuracy for ordinary purposes. The experiments of Pambour are said to confirm the law of Watt, inasmuch as steam, "under an absolute pressure, varying from 2-7 to 4'4 atmospheres, and escaping into the atmosphere under an actual pressure of from 14 to 1-03 atmosphere, presented at its issue exactly the same temperature as though it were saturated." for non-condensing engines, 10000,,. u = (o) 1-421 +-0023 v' where u is the relative volume, or the ratio of the volume of the steam to that occupied hy the same weight of water, and p the pressure expressed in pounds per square foot. here P is the pressure in lbs. per square inch, and V its relative volume compared with that of its constituent water. Mr. Pole observes, that this formula may be adopted without considerable error throughout the range generally required in the Cornish engines, viz. from 65 lbs. to 5 lbs. per square inch. Now, if we suppose a volume of water E to be converted into steam at a pressure p, and if M be the volume of steam which can be produced by it, then u =---= (d) E a. + $p If, again, the same volume of water be converted into steam at a pressure p', and M' is the absolute volume of steam at that time, we shall have M' 1 E a + &p' therefore, between the absolute volumes of steam which correspond to the same weight of water, we shall obtain, by eliminating E, the relation a and jS are the constants in Pambour's formula. Now, by proceeding in the same manner with Pole's formula, we obtain the ratio of the volumes On the Work done by the Engine on the Piston, per minute. Let E represent t...