1824.] On the Transmission of Electricity through Fluids. 283 



Article X. 



On the Effects of transmitting the Electrical through other Fluids. 

 By Mr. C. Woodward. 



(To the Editor of the Annals of Philosophy.) 



SIR ? March 12, 1824. 



As every subject connected with electrical science is daily 

 assuming a more important feature, the following experiments 

 and observations may not be uninteresting to some of your 

 readers. 



Place apiece of glass on the table of the universal discharger, 

 and bring the pointed wires nearly in contact upon the surface 

 of the glass; over the intersection formed by the wires, strew 

 some loose gunpowder, and pass through it the charge of a jar 

 containing about a square foot of coated surface, when it will be 

 found that the powder will be invariably dispersed without 

 inflammation. 



Take a glass tube six or eight inches long, and about a quarter 

 of an inch in diameter, fill it with water, and insert a cork at 

 each end ; through the corks pass pieces of wire so as to form a 

 conducting communication with the water ; place some loose 

 gunpowder on the glass of the universal discharger as before, 

 insulate the tube, and let it form part of the circuit ; pass the 

 charge through the water, and the gunpowder will be inflamed. 



The small degree of intensity of charge required to produce 

 the inflammation of gunpowder, when transmitted through a 

 tube of water, is surprising ; as the discharge of a quart jar 

 indicating only an intensity of from 10 to 15 degrees is generally 

 sufficient, and there appears to be little or no difference in the 

 effects of tubes varying from 3 to 18 inches in length. 



In prosecuting my inquiries to ascertain the cause of this sin- 

 gular effect, I found that the charge of a jar, which, when 

 transmitted by a;ood conductors, was sufficient to produce the 

 fusion of 12 inches of iron wire, did not affect a single inch of 

 the same wire, when passed through the tube of water ; from 

 which I concluded, that the intervention of the water tube, must 

 have produced or prevented some mechanical effect. 



I then pasted on a board, about three feet long, a narrow slip 

 of tin foil, in which, at equal distances, four intersections, about 

 one-eighth of an inch each, were made. I insulated the board, 

 and placed over one of the intersections some loose gunpowder, 

 and over each of the others six or eight wafers. On transmit- 

 ting in the common way a charge through the tin foil, the pow- 

 der was scattered, and the wafers blown three or four feet from 



