246 TRANSACTIONS OF THE AMERICAN INSTITUTE, 



properly constructed, was equal to the gases rising from moist 

 hay, as it was put up. in barns in the country, and which was the 

 cause of their frequent destruction. 



Mr. Quimby thought that a rod properly put up was sufficient 

 to ensure the safety of the barn in this case, and his experience 

 abundantly confirmed him in this belief. To an inquiry as to 

 how he would put up a rod on a barn thirty feet square, Mr. 

 Quimby said it would depend some on the nature of the soil — as 

 to whether it was very dry or moist. If the ground was tolera- 

 bly moist, it would be advisable to have rods at, at least, 

 three corners of the building, to be connected by rods lying on 

 the roof. He said he very nearly concurred with Prof. Henry, 

 with the exception of the necessity of continuity of metal in the 

 rod. • The firm of which he was a member had found by experi- 

 ence that a mere contact, by screws or otherwise, was sufficient. 

 The practice of insulation had arisen from a misconception of 

 conditions incident to a discharge of lightning. All the glass in 

 the world could not alter these conditions. The building has to 

 receive or give off, as the case may be, a certain quantity of elec- 

 tricity ; the question was, how shall the equilibrium be restored ? 

 by an explosion of electricity accumulated in sufficient force to 

 overcome the insulation, or by means of the intimate connection 

 of the rod with all parts of the building whereby a rapid distri- 

 bution is effected, and the fluid in its rapid state can circulate 

 freely and silently in all directions. 



Mr. Lyon argued in opposition to some of the ideas advanced 

 by Mr. Quimby. He said if a building could have a perfect con- 

 ducting power in all its parts, damage from lightning would be 

 unknown. Among the many magazines of Europe, which are 

 built of iron, there has never been an instance of their being 

 struck by lightning. A man encased in armor is perfectly safe 

 in a thunderstorm. He considered that there was one kind of 

 electricity in the clouds, and another kind in the earth, when 

 these tAvo forces come together there was a concussion. The 

 object of a conductor was to bring these forces together easily 

 a;nd without concussion. If our houses were covered with metal 

 there would be no danger from lightning. His opinion was there- 

 fore in favor of insulators. 



Mr. Quimby said that his firm had the experience of twenty- 

 five years of entire success to confirm them in the disuse of insu- 

 lators ; and their rods had insured safety, while many buildings 



