Instance of Human Effort.—Six Days’ Sawing
A Pair of sawyers, in the yard of Messrs. Paul, and Co., timber-merchants, Broad-street, Golden-square, executed the following quantity of labour in sixty working-hours, in six days, beginning about eight, a.m., on Monday, the 25th, and ending about four, p.m., on the following Saturday, the 30th of January, in the present year.
They sawed through an area of 3068 square feet of American Pine, along a line whose total length was 1726 feet. In doing this, they raised the saw 124,272 times, and as this tool weighed 30 lbs., they lifted an actual weight of 3,728,160 lbs. But this amount of labour was not more than one-third the actual exertion expended; for to overcome the friction, in pulling up the saw through the kerf, and forcing it down again through the wood, at least two thirds more was necessary; the total labour, therefore, was equal to lifting 11,184,480 lbs. to the height of the stroke, and as this was four feet, there was 44,737,020 lbs.= 19,958 tons. 18 cwt. raised one foot high, in 60 hours, which is 12,427 lbs. = 5 tons, 11 cwt. raised one foot high, per minute, by the two men, and 2 tons, 15½ cwt, per man, 1 foot high per minute.
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