894 Transactions of the American Institute. 



secouds, the pile meanwhile moving upward very reluctantly at tho 

 rate of only one-twelfth of an inch per minute. 



The experiment of trying 40, 41, 41^ tons occupied half an hour, 

 during which time the strain being incessant, the pile was moved 

 two and a half inches. 



This same pile was then subjected to a strain of thirty tons for 

 eighteen hours, and was not moved by it. After which, by increas- 

 ing from thirty-two to thirty-seven tons, the pile was moved in one 

 hour, three inches, and after it had been moved upward about six 

 inches, a lifting power of twenty-five tons continued to remain on 

 it for two days, and did not move it. Commodore Newton then 

 pronounced the experiment complete. 



This pile was then wholly withdrawn from the sand, and its 

 dimensions, &c. were found to be as follows: Material, yellow 

 pine of Florida; extreme length, twenty-nine feet, perfectly straight; 

 in sand, including sharpened point, two feet long, sixteen feet; 

 weight of the pile, 1,632 pounds. 



The bark remained on the entire pile, except three and a half 

 feet of its point; it was somewhat smoothed apparently by the 

 friction of the sand. 



There was no sand adhering to the pile, except on the sides of 

 the sharpened point; here was a little brown-colored sand stuck on 

 very hard; it appeared like sand mixed with the turpentine of the 

 wood. 



The probability is, this pile would have resisted a much greater 

 strain than forty tons, had it been applied more steadily, and with- 

 out jarring the lever, and had all the work of pile-driving in the 

 vicinity been stopped. The blows of the pile hammers being used, 

 jarred the crust of the earth for several hundred feet around. 



A single foundation pile similar to that drawn out, was used as 

 a fulcrum, and sustained without settlement 38 -^^^ tons, much less 

 than its full bearing capacity. It gives us, however, a fact. 



The United States fortification, named " Fort Montgomery " (Lake 

 Champlain), is entirely founded on piles. The bottom was nothing 

 unusual, in fact an ordinary average of a mud bottom, such as is 

 found in the edge of a lake immediately bounded by a swamp. < 



The piles there, were of an average length of thirty-one feet, 

 average diameter twelve inches, They were driven about thirty 

 feet into the earth, by a ram weighing 1,630 pounds, falling the 

 last blows thirty-three to thirty-six feet. 



