170 



Committee would therefore decide the second question in the 

 negative. 



3, Whose rods, and of what construction have afforded the 

 greatest security 1 



The best rods or those which have stood longest the test of 

 time were invented by King Solomon ; for the temple, was 

 unharmed by lightning during one thousand years. The whole 

 roof bristled with metallic pinnacles, the body of the buikling 

 was covered with plates of gold, and water spouts from the roof 

 descended into deep cisterns of water. This was the system of 

 Solomon. 



If then we elevate a sufficient number of points to furnish a 

 passage for the electric flood, and with surface sufficient to 

 prevent any part of it from seizing some iron bar, zinc roof, 

 tinned porch or window-casing, we have complied with one 

 essential condition ; if we keep open a sufficient number of these 

 passages to the earth, and spread the rods into points below as 

 above, we have answered another condition. If different parts 

 of the house are furnished with metals, these substances should 

 be united by wires with one of the main trunks ; if, however, 

 we insulate the system of conductors, furnish a sufficient num- 

 ber of them, and thus prevent the fluid from reaching the 

 imperfect conductors within the building, we shall have 

 answered the same purpose. 



An excellent system of conduction for our buildings is that 

 of George W. Otis ; for ships that of W. G. Harris. 



The rods of the former are constructed from 3-8 in. iron 

 elevated above each chimney, the points of the ridge pole and 

 other prominent elevations, presenting either a branch of points 

 or a single point, gilt, extending over the ridge-pole down the 

 rafters to the earth, united with a screw and socket, and insu- 

 lated from the building by means of glass cups. 



That of Mr. Harris, consists of a double strip of copper, 

 sunk into each mast and spar by a shallow channel, to bring 

 the metal flush with the wood ; the strip being interrupted at 

 every few feet to give way readily with the bending of the 

 spar, and still so as to preserve its continuous extension. The 

 strips extend from the mizen mast to the stern-post, from the 

 steps of the mast to the metallic bolts passing through kelson 

 and keel to the water ; also bands of copper pass under the 

 beams leading to the iron knees or metallic fastenings, passing 

 through the side of the ship, the whole formed with shut joints, 

 and making of the ship a compound metallic mass, little liable 



