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XXXVII. On the Electricity of Condensation. 

 By Reuben Phillips, Esq. 



To the Editors of the Philosophical Magazine and Journal. 



Gentlemen, 



I FIND I have not been sufficiently explicit in giving my 

 views of the forces concerned in the production of the 

 electricity of condensation, and I perceive this from the ques- 

 tion put by Mr. Birt, page 171 of the last Number of the 

 Philosophical Magazine, namely, "Would the condensation or 

 running together of the vapour particles cause an increase of 

 tension ?" Or as the question may be put. Is the electric ten- 

 sion really observed in experiments of the electricity of con- 

 densation only equal to, or less than, that of the electric ten- 

 sion of the molecules when first condensed ? 



It is shown (11.) that a jet of steam escaping into the air 

 acts on a magnet like an electric current, and (26, 29.) suffi- 

 ciently shows this effijct to be occasioned by the condensation 

 of steam, and for the reasons detailed (32.) these electric cur- 

 rents must be of a discontinuous molecular nature: or in 

 other words, we have one set of particles positive and the 

 other negative, with currents between them; unless, indeed, 

 we suppose the resistance to the currents to be nothing, in 

 which case the phaenomenon would be entirely detached from 

 what I have called the electricity of condensation. I have 

 found that when drops of water are driven through this mag- 

 netic jet of steam {55^ 56, &c.), the drops become powerfully 

 electrified positively, at the same time the steam and water 

 together may be very neutral, as in some experiments with 

 the gun-barrel (58.), and could doubtless be made as nearly 

 neutral as we please; therefore the particles of water being 

 positive, another set of particles must have an equivalent ne- 

 gative charge. It is, I think, impossible for the drops of water 

 to have become charged in any other way than by taking on 

 themselves some of the positive electricity previously belonging 

 to the particles concerned in producing the magnetic effect. 

 Thus it is seen that the addition of drops of water to the con- 

 densing steam has only altered the general slate of affairs by 

 effecting a sort of separation between the positive and negative 

 particles. 



It now remains to point out that the electric tension derived 

 from these aqueous drops is much higher than that of the 

 positive molecules from which the charge was obtained. 



The electric charge communicated to the electrometer by 

 the steam in such experiments as those of (52, 56.) was so 

 strong, that although I have not performed the experiment, 



