1820.] Mathematical Principles of Chemical Philosophy. 145 



the metals, this cause would be quite adequate to the production 

 of the observed effect. Besides, had the brass dust lost any of 

 its capacity for heat by the operation, this must have been very 

 nearly, if not entirely, restored by the subsequent treatment ; for 

 after it had been separated from the solid metal by friction, it 

 was exposed for a considerable length of time to the extreme 

 heat of the interior of the cylinder, and was afterwards heated, 

 in order to ascertain its capacity : by which means it is well 

 known its specific gravity and capacity for heat would be 

 restored, at least in a very considerable degree. The greatest 

 error appears to be the assumption that the source of the heat 

 thus generated is inexhaustible ; the quantity that can be thus 

 excited is finite. Let the end of a thin bar of soft iron be sub- 

 mitted to repeated blows of the hammer, it soon becomes 

 ignited ; let the operation be continued, the heat gradually 

 abates, and soon ceases entirely, after which it cannot be 

 brought into an ignited state by the same process without being 

 previously exposed to the fire. This is a process decidedly the 

 same as that of Count Rumford in its principle, but entirely 

 opposes the conclusions which he drew from his own experi- 

 ment ; he would have doubtless come to the same conclusioa 

 had his experiments been continued so long that the whole mass 

 of metal employed had been brought to the greatest density, to 

 which the friction used could have brought it ; but since this 

 was not the case, it is evident that the whole quantity of heat 

 which the metal used could have furnished was not obtained. 



On account of the complexity of this hypothesis, its incapabi- 

 lity of explaining the phenomena of nature, and the impossibility 

 of such motions taking place in consequence of the operation of 

 those forces which are known to be inherent in matter, I shall ia 

 the succeeding papers assume caloric to be an elastic fluid, and 

 from its effect joined to that of the centripetal force which 

 Newton has demonstrated to exist, explain most of the primary 

 laws of chemical and corpuscular action. 



( To be continued.) 



Article IV. 



Proceedings of Philosophical Societies. 



ROYAL SOCIETY. 



Dr. WoUaston has been elected President of the Society, 

 ad interim. 



June 29. — A paper by Dr. WoUaston was read, entitled, 

 " On sounds inaudible by certain Ears." The author, after 

 some introductory remarks, proceeded to describe a peculiar 



Vol. XVI. N° II. K 



