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LXX. Some Remarks on the Theory of Thunder-storms. 

 By Reuben Phillips, Esq. 



To the Editors of the Philosophical Magazine and Journal. 



Gentlemen, 



I THINK it necessary to offer the following remarks on 

 Mr. Peter Clare's theory of thunder-storms, page 334 of 

 your last Number. 



Passing over the confusion which exists in the use made of 

 the terms "quantity or intensity," I would especially direct 

 attention to the following grave objections : — 



1. There are no experiments which show that steam can 

 absorb electricity, and render it latent in a manner analogous 

 to latent heat, or in any other way. 



2. No source is assigned whence the electricity is to come 

 to satisfy this capacity for electricity. 



3. The theory requires the production of positive electricity 

 without negative. 



Then with regard to the theory of rain, page 335, it is for- 

 gotten that, in the interior of a cloud, each particle is simi- 

 larly related to surrounding particles, and that consequently 

 they do not move each other in the way supposed. The truth 

 is, the whole electrical force of the cloud is thrown upon the 

 surface of the cloud, as was long ago pointed out by Dr. 

 Faraday*. From which it follows, that aerial condensations 

 must occur in the lines of electrical induction; but, judging 

 from the appearances of a thunder-storm, these condensations 

 are so small in amount as to be incapable of producing those 

 effects which Mr. Clare suggests, although sufficient, as has 

 been long supposed, to produce winds and move clouds. 

 Mr. Clare also forgets that rain precedes the flash of lightning. 



Evaporation has sometimes been supposed to generate elec- 

 tricity ; but it having been found by Mr. Armstrong, a result 

 subsequently confirmed by Dr. Faraday, that. by allowing the 

 steam to escape, as on removing the safety-valve from a boiler, 

 no electricity is obtained, it appears necessary to abandon the 

 idea, and to agree to consider, with M. Peltier, that the elec- 

 tricity apparently produced by evaporation under certain cir- 

 cumstances must be ascribed to other causes, such as the decre- 

 pitation and projection of saline matter; and in experiments 

 where pure water only is used, to friction between the water 

 and other bodies, steam or particles of water carrying off one 

 species of electricity. 



The theory of atmospheric electricity which I have ven- 



* Phil. Mag. vol. xxii. p. 203. 



