AMERICAN INSTITUTE. 621 



and it may result from the experiment that the surf ce of this 

 pebbly kind of rock, may wear rough, and in this respect avoid 

 the objection of danger to animals; but I think it can never com- 

 pare with the Jersey Trap, of the Belgian sized blocks, in point of 

 durability and economy. 



Mr. Clough exhibited and explained Estlake's patent invention 

 for preventing damage to goods by water, in case of fire, patented 

 June Stli, 1856. A model brick building, five stories high, with 

 water pipes adjacent, throwing water into each story, as may be 

 required, and as it accumulates on the floor, running oft' at a 

 corner prepared to receive it, and pour into the street. So that 

 although goods are wetted sufficiently to extinguish fire, they are 

 not left soaking for hours. The floor to be laid with a slight in- 

 clination to the point of delivery, three inches to one hundred 

 feet. 



The subject of laying the submarine electric cable, being under 

 consideration — 



Mr. Hildreth, who was present at the last meeting of the 

 Mechanics' Club, asked permission to make a few remarks, in 

 relation to a paper read by the Secretary, from the association of 

 civil engineers of London, concerning the electric subinarine cable. 

 He said that, in that paper, the success of telegraphing from 

 Gal way to Newfoundland was predicated upon an experiment 

 made in England, of sending a current of electricity through two 

 thousand miles of wire. The experiments of Michael Faraday 

 had shown that, in water, the electric current had to encounter a 

 resistance (\'hich was equal to three times the distance through 

 the atmosphere; and that no calculation had been made for the 

 inequalities of the bed of the ocean, which the rocky coasts of 

 Ireland and America would indicate that it would be equal to 

 nearly three times the actual linear distance from coast to coast, 

 making a resistance to be overcome equal to the distance of twenty- 

 seven thousand miles of wire through the atmosphere. Mr. Hil- 

 dreth concluded that we ought not to be too sanguine of the 

 success of the first experiment of laying the submarine cable. 



