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(400 oz. in weight,) and the generation of electricity was as abundant 

 as when they employed an oxidizable metal. The electricity was 

 also evolved by the insulated operator simply holding his hand in the 

 steam as it issued ; in which case the steam was condensed upon the 

 hand, and the whole person became charged. Dr. Patterson stated, 

 that this was, in fact, the experiment accidentally made near New 

 Castle, in England, and which has attracted so much attention. 



To show that the electricity was not caused by the rushing of the 

 vapour through the air, Dr. Patterson said, that an apparatus was 

 made, consisting of a pipe connected with the stop-cock on the boiler, 

 a portion of about ten inches in length, near the upper end, being of 

 glass, to produce insulation, and the remainder of lead, wound into a 

 helix, like the worm of a still. This helix was immersed in a bucket 

 of water and snow. When the steam was admitted, it became entire- 

 ly condensed within the pipe, so that there was no rush through the 

 air; yet the production of electricity was as abundant as with the for- 

 mer arrangements. 



Dr. Patterson took notice of experiments made, half a century ago, 

 by Volta and Saussure, and afterwards by Cavallo, which proved, to 

 their satisfaction, that electricity was evolved during evaporation and 

 condensation, but which have since been called in question by Pouil- 

 let and others, who assert, that a mere change of state, not accompa- 

 nied by chemical change, never gives rise to electricity. He con- 

 sidered the experiments, now made on a large scale, as favouring, if 

 not confirming, the first opinions entertained on this subject. 



Dr. Patterson referred to the satisfactory manner in which these 

 new experiments seem to explain the sources of electricity in the thun- 

 der storm, and in volcanic eruptions. 



He then related an experiment in which an insulated iron ball, and 

 afterwards a bar of gold, was heated, and a small stream of water 

 poured on it, so as to be formed into steam at its surface. The first 

 experiments seemed to show that the metal was charged with nega- 

 tive electricity, but subsequent trials threw doubts upon this conclu- 

 sion. 



Dr. Patterson also described experiments made to determine whe- 

 ther electricity was given off during the solidification of liquids, — the 

 substances used being melted lead, silver and gold. In every case, 

 however, the gold-leaf electroscope failed to exhibit the presence of 

 any electricity. 



Prof. Henry stated that he had not seen the sparks from steam ; but 



