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tion of coal in a stove. But what, he asked, is the source of electri- 

 city in this case? Is it combustion, the evaporation of the moisture, 

 or the friction of the hot air on the interior of the pipe? 



Dr. Goddard stated, that in the case of a stove, pretty well insulated, 

 his family had amused themselves with drawing sparks half an inch 

 or three quarters of an inch long; and that similar sparks were ob- 

 tained from the frame of a looking-glass over an open grate, in the 

 house of Dr. Norris, of this city. 



Professor Bache remarked, that in the case referred to by Prof. 

 Henry, in which sparks of electricity were obtained from a stove, he 

 had satisfied himself that these were owing to the experimenter wear- 

 ing a silken shirt : — an experimenter, not similarly clad, being unsuc- 

 cessful. 



Dr. Hare ascribed the incredulity and the opinions which he had 

 expressed, when this subject was brought before the Society by Mr. 

 Peale, at the last meeting, to a misapprehension, on his part, as 

 to the circumstances. He considered that the fact of electricity being 

 developed in the case adduced was established. He alluded to the 

 almost incredible case of a lady, who, agreeably to evidence men- 

 tioned in Silliman's Journal, gave off sparks of electricity. He stated 

 also the result of an experiment to discover whether electricity was 

 given off during the rapid evaporation of a saline solution. There 

 was no evidence of excitement. The vessel was of glass. 



Mr. Lea had frequently observed sparks from a common grate. 



In reference to the results of experiments by Dr. Patterson, in which 

 no evidence of the development of electricity was observed in metals, 

 whilst undergoing a change from the liquid to the solid state, Dr. 

 Goddard observed, that in cases of crystallization on the large scale, 

 as of nitre, in the extensive chemical works of Mr. Wetherill, a beau- 

 tiful flash of electrical light was apparent. 



Professor Rogers suggested, that in ordinary combustion there may 

 be a constant development of electricity, and that means may possibly 

 be found to render it apparent by perfect insulation. 



Professor Henry stated, that Pouillet had found that electricity is 

 developed by the combustion of charcoal, and he offered some sugges- 

 tions as to the mode of rendering the electricity, given off from a stove, 

 apparent, by insulating it both above and below. 



Dr. Emerson thought, that the change of state from solid to liquid, 

 and from liquid to solid, might account for various electrical pheno- 

 mena presented by the animal body. Dr. Hare suggested the diffi- 



