THE YOUNG FARMER'S MANUAL. 439 



be so lajge and speed-pulley so small, (in a one or two-horse 

 power, J*Il; to absorb all the available power in getting up a good 

 velocity. These should be just large enough to allow the horses 

 ove with their ordinary gait. Intimately connected with 

 subject, as elucidating and rendering it more intelligible, is 



tins s 



THE INFLUENCE OF THE THICKNESS OF THE MATERIALS 

 TO BE SAWED. 



681. Every one who has ever sawed a board in two with a 

 hand-saw knows that it will require three times more time and 

 power to saw off a board one foot wide, if the saw be made to 

 cut entirely across the width of the board, than it does to saw it 

 having the saw cut only across the thickness of the board at once. 

 A man will saw in two with a hand-saw twelve boards one foot 

 wide and an inch thick, twice as quick as he can saw in two a 

 stick of timber one foot square. A man will saw with a slitting- 

 saw, eight feet in length of a board one inch thick, quicker and 

 easier than he can saw one foot in length of a four-inch plank 

 with the same saw, unless the teeth were very coarse. 



682. In sawing fire-wood with a two-horse-power, if the wood 

 be nearly all from six to eight inches thick, by splitting it in two 

 before sawing it can be sawed with the same power in about half 

 the time that it would require, without being made smaller. 

 With an abundance of power a cord of large wood could be sawed 

 sooner than a cord of small wood. A span of horses on a two- 

 horse railway power will do a good business at slitting boards 

 and plank from one and a half to three inches thick. As the 

 thickness of materials to be sawed increases, in order to do a fair 

 business an increase of power is necessary. With a circular saw 

 about one foot in diameter, driven by two horses, a man can saw 

 seventy feet in length of hard lumber one inch thick if he is able 

 to handle the lumber as fast as the saw will cut it sooner than he 

 can saw through a plank twelve feet long and three inches thick. 



683. A circular saw ten or twelve inches in diameter, for slit 

 ting boards and two-inch plank, will do much neater and smoother 

 work than a saw twice as large in diameter. This is particularly 



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