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England had been successfully repeated by Mr. Peale, Mr. 

 Saxton, and himself, at the United States' Mint 



Dr. Patterson said, that their first attempts were to collect elec- 

 tricity from the steam as it issued from a gauge-cock, near the sur- 

 face of the water, in the boiler; but in this case the steam was always 

 accompanied by a spray of water, and the experiments failed. They 

 also failed when the steam was of a low temperature, as it was then 

 condensed immediately upon leaving the boiler, so as to form a cloud 

 of vesicular vapour. In both these cases, the electricity, if evolved 

 at all, would be led back to the boiler — the spray and the vesicular 

 vapour being, as is well known, electrical conductors. 



When, on the other hand, high steam was drawn off from a stop- 

 cock far removed from the water in the boiler, it was observed to 

 issue, for some distance, in the form of a transparent gaseous vapour, 

 and, in this case, any insulated body on which it was condensed was 

 always found to be charged with electricity. Thus, if the experi- 

 menter stood on an insulating stool, or even on a box or ladder of 

 dry wood, and held an iron ladle, or any other conductor, in the is- 

 suing steam, the conductor and the operator became so fully charged 

 with electricity, that thick sparks of a half, three-quarters, and in 

 some instances a whole inch in length, were drawn off; the Leyden 

 jar charged; the shock given to several persons holding hands, &c. 

 The electricity thus produced was found to be always positive. 



Dr. Patterson said, that one of the most important conclusions to 

 which the experiments had led, was, that true gaseous steam is a 

 non-conductor of electricity. If it had not been so, the apparatus 

 would not have been insulated, and the electricity excited would have 

 been carried back to the metallic boiler, and thence to the earth. 



Dr. Patterson thought it most probable that the electricity, in these 

 experiments, was evolved by the condensation of the steam — the phe- 

 nomenon being analogous to the evolution of latent heat by the same 

 condensation. He remarked, that as the steam within the boiler was 

 surrounded by conductors, it could not be supposed to contain free 

 electricity, and that on leaving the boiler, the only sources to which 

 the electricity could be ascribed, seemed to be the condensation of the 

 steam, the oxidation of the iron against which it impinges, or the fric- 

 tion of the steam against the air as it rushes through it. 



To shew that oxidation was not the source of the electricity, the 

 experimenters caused the steam to strike upon a large bar of fine gold 



