An examination of Dr. Crawford's theory of heat and combustion / by William Morgan.
- William Morgan
- Date:
- 1781
Licence: Public Domain Mark
Credit: An examination of Dr. Crawford's theory of heat and combustion / by William Morgan. Source: Wellcome Collection.
Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.
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![[ <2 ] “ mofphere in the firft minute, fay as 84 to 89 *l fo is 94 to a fourth proportional *, which ** gives 99.5 : From whence it appears that 5^ “ degrees weie carried oft' by the air in the “ firft minute.- Adding 57 to 155 we have “ 160.5 f°r lhe true temperature of the water “ and the veftcl. Subtracting this from 168 “ we have 7.5 tor the remainder. The water “ was therefore cooled by the veftcl 750, and “ the veftcl was heated by the water 92°.5 : “ And fince the veftel received this heat from “ the water, it is manifeft that the fame quan- “ tity of heat which changes the temperature of “ one pound of water 7.5 will change the tem- “ perature of the veftel 92.5. And by a parity tc of real'oning the fame heat which raifes the “ water one degree will raife the veftel i2f * The author in computing the heat which is loft in the firft minute adopts a rule which is faid to be given by Sir lfaac Newton, who confidering the heat of a body as the cxcefs whereby it is warmer than the furrounding medium, fuppofed that the quantities of heat loft in fmall portion^ of time would always be proportional to the heats remain- ing, and therefore if the times were taken in arithmetic progreflion the decrements of heat would be in geometrjc progreflion. 1 would further obferve that the numbers 94, 89 and 84 are found by fubtratting 6r, the tempera- ture of the atmofphere, from 155, 150 and 145, the fe- vrral degrees of heat at the end of the ift, 2d, and jd minutes. “ degrees.](https://iiif.wellcomecollection.org/image/b21513958_0018.jp2/full/800%2C/0/default.jpg)
