308 I J'R^tEKTlON OF DAMAGE BY LIGHTNING. 



to pfbve the best conductors, he found the same charge frotn 

 an electric machine melted 4 incliesof gold wire, 6 inches of 

 brass wire, 8 inches of silvered copper, 10 inches of silver, 

 and 10 inches of iron wire; so that gold is the best con- 

 ductor, and iron the worst. Brass stands next to gold in 

 . the quality of a conductor. Cavullo says, that copper and 

 brass are the best conductors, and also that they never rust ; 

 but to make them of copper or brass would be a very great 

 expense, and then, if not drawn through plates, they would 

 be very uneven on the surface, which is a defect in electric 

 rods. 

 Iron tubes J had in prosfject the making of conductors on an im- 



plated Willi proved plan, so that they would be equal to solid brass ia 

 their use, and come as cheap or cheaper than wrought iron, 

 in a patent T have very recently obtained for combining dif- 

 ferent sorts of metals, particularly brass or copper, with iron. 

 By this method we can plate or cover tubes of iron 15 or l6 

 fdet long, of any diameter, with a coat of brass, from -r^ ^^ 

 an inch, to any thickness ; and so connected with the iron, by 

 compression, that, when so combined, it appears a solid piece 

 ' ■ of brass, but being hollow, is very light and portable, and 



the method used in making them being by drawing them 

 , through a polished draw phite, all the surfaces are as smooth 

 and uniform as it is possible to make them. B^ing made 

 in convenient lengths, they may be sent to any part of the 

 kingdo«i, and put up in a very shorti time, as one piece screws 

 into another, so that, when screwed in, both edges of the 

 brass meet, and join together. Conductors of this kind 

 would never rust, as what is presented to the atmosphere is 

 brass only. They would be 4 lighter than iron rods, would 

 be put up in a very short time, would be quite as cheap as 

 iron, and furthermore would be the best conductors you can 

 possibly make. But as I said before that I had given the 

 subject a good deal of thought, especially the probability 

 of drawing off the electric matter by conductors, so as to| 

 prevent its getting to a head and causing by its discharge sa 

 many accidents ; when I considered the manner of the iron! 

 rods and their great defects, it set me a thinking how I could 

 contrive a better conductor than iron, and I flatter myself I 

 have succeeded. Therefore I leave it to every man to judged 



whether 



