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How THE FARM PAYS. 



A ton of mixed Timothy and Clover measures 520 feet. 

 A ton of mixed meadow grasses measures 600 feet. 

 A ton of loose straw measures 900 feet. 



STRENGTH OF ROPES. 



A good rope will sustain a weight in pounds equal to the numoer 

 of the square of the circumference in inches, multiplied by 200. Thus 

 a rope 3 inches in circumference, or 1 inch in thickness, will sustain 

 1,800 pounds with safety. (For instance, 3X3=9X200=1,800.) This 

 would be equal to the draft strength of 12 horses. 



WEIGHT OF LEAD PIPES PER FOOT. 



One foot of 1-inch round iron rod weighs. ... 2.63 Ibs. 

 square " " " 3.36 " 



For lesser sizes divide the weight by four, for half the size, and for 

 larger, multiply by four, for twice the size. 



MAN AND HORSE POWER. 



An average man can draw a weight of 27J- pounds over a pulley at 

 the rate of 220 feet per minute. 



An average horse can draw a weight of 150 pounds over a pulley 

 for a depth of 220 feet in one minute. This is equivalent to raising 

 33,000 pounds one foot high in a minute, and is a standard horse- 

 power. 



To find the horse-power of a steam engine, multiply the pressure 

 of steam per inch by the area in inches of the cylinder; multiply 

 this product by the length of the stroke in feet, and this 

 product by the number of strokes per minute ; divide the result by 

 33,000. Thus, an engine working at 30 pounds pressure per inch, 

 with a cylinder of 8f inches diameter, and 55 square inches area of 



