400 



Farm Mechanics. 



It is not safe, however, to have a horse repeat such 

 strains as this often nor maintain them long at a time. 

 Even when a horse is pulling with an intensity of one- 

 fourth its weight this is too heavy for steady work and rep- 

 resents 



For a 1,600-lb. horse, 2f H. P. 



For a 1,200-lb. horse, 2 H. P. 



For a 1,000-lb. horse, If H. P. 



For an 800-lb. horse, 1| H. P. 



Indeed, it is commonly allowed that for steady and con- 

 tinuous work 10 hours per day at the rate of 2.5 miles per 

 hour a horse should not he asked to pull more than \ to 

 tV of its own weight. At this rate the work of horses 

 of different weights would be 



For a 1, 600-pound horse, 1.06 to 1.33 H. P. 



For a 1,400-pound horse, .93 to 1.17 H. P. 



For a 1,200-pound horse, .80 to 1.00 H. P. 



For a 1,000-pound horse, .67 to .83 H. P. 



For an 800-pound horse, .53 to .67 H. P. 



610. Horse Power Required to Haul Loads on a Wagon 

 Taking 1 H. P. equal to 550 foot-pounds per second and 

 the data in the table of (538), the number of horse power 

 required to haul two tons, including the weight of the 

 wagon, under the conditions there stated, are given in the 

 table below : 



Table giving the number of H. P. required to haul $ tons on 

 wagons under different conditions, when the rate of travel 

 is .5 miles per hour. 



