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. 1810 Excerpt: ...which obtains on the immersion of the apparatus in a liquid mass. Since the discharge of heat by external pulsation is now precluded, the nature of the extreme boundary, will have no influence whatever on the measure of effect. This result must depend almost entirely on the quality, the position, and the number of the ...
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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. 1810 Excerpt: ...which obtains on the immersion of the apparatus in a liquid mass. Since the discharge of heat by external pulsation is now precluded, the nature of the extreme boundary, will have no influence whatever on the measure of effect. This result must depend almost entirely on the quality, the position, and the number of the interior surfaces f. "A cylindrical canister of planished tin, three inches in diameter and height, and which in still air takes 117' to cool, from 20 to 10 would require 249' if included regularly within a similar cylinder of four inches, but only 185' if the whole were immersed in a tub of water. The same canister when painted, would, in a close room, cool in 61', or, surrounded with its case likewise painted, in 98', and both plunged in water would take only 64'. Page 394. f P-ge s96. "In all these examples, the canister and its several cases are regularly separated from each other by intervals of half an inch. If the divisions approach nearer, their effect soon becomes altered; for the successive strata of intercluded air as they diminish in thickness, lose in some degree their internal mobility, and begin passively to transmit heat like a solid mass. When the terminating surfaces mutually approximate, not only is the fluidity of the thin shells of air proportionally cramped, but the power of communication is likewise invigorated by the shortness of the passage, and consequently the quicker gradation of temperature. On both these accounts, therefore, the quantity of transmission will increase with most rapid progress, as the septa contract their limits. Thus, a cylindrical tin canister of three inches in diameter and height, placed within a similar one of four inches, will cool about one-sixtieth part faster, if shifted from...
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