348 Mr Eowell on the Electricity of Steam. 



having a greater capacity for electricity, they are buoyed up 

 by their coating of electricity as a bullet may be buoyed up 

 in water by a coating of cork, and that no evaporation at low 

 temperatures could go on without electricity ; that the vapour 

 so raised into the air, when condensed, becomes surcharged 

 with electricity, and thus remains suspended until the sur- 

 charge escapes, either as lightning, or else imperceptibly, to 

 the earth, when the remaining coating of electricity being 

 insufficient to buoy up the particles of vapour, they fall as 

 rain, &c. ; and that it is possible to cause rain at will by 

 raising electrical conductors to the clouds, by means of bal- 

 loons, and thus enabling the surcharge of electricity in the 

 clouds to escape to the earth. 



The discovery of the electricity of steam I considered a 

 strong support of these opinions ; but a theory having been 

 proposed by Dr Faraday, who explained the electricity of 

 steam as caused by the friction of particles of water carried 

 along by the steam rubbing against the solid matter of the 

 passage through which the steam is escaping from the boiler, 

 — the following is an attempt to shew that the electricity of 

 steam is not caused by friction, but by its expansion, on 

 escaping from the boiler, thus carrying off electricity, and 

 rendering the boiler (if insulated) negative, the steam again 

 giving off its positive electricity when condensed ; and that 

 the phenomena of Dr Faraday's experiments will sunport this 

 hypothesis. 



One experiment, which I believe tells against the theory 

 of friction is as follows : — " An insulated wire was held in the 

 stream of steam issuing from a glass or metal tube, about half 

 an inch from the mouth of the tube, and was found to be un- 

 excited; on moving it in one direction, a little further off, it 

 was rendered positive, on moving it in the other direction, 

 nearer to the tube, it was negativeP In addition to this, both 

 Mr Armstrong and Mr Pattison, in their experiments, found 

 the greatest development of electricity at some distance from 

 the boiler, in some cases five or six feet. 



I cannot conceive how this phenomenon can take place 

 if the excitement is caused by friction of the particles of water 

 in the tube, as in that case I believe the strongest develop- 

 ment of electricity would be at the mouth of the tube or 



