EFFICIENCY OF THE HORSE 37 



the farmer understand and meet the food needs of the 

 horse as accurately as the engineer meets the fuel needs of his 

 engine. 



The thermal efficiency of a motor is, however, not a true 

 test of its value to the farmer. The economy or commercial 

 efficiency is of more practical moment. From the investigations 

 at Halstad, Minn., we find the average farm value of food 

 alone to be 4.3 cents for each hour of horse labor throughout 

 the year. On the basis of 4.5 h.p. developed, the cost of fuel 

 per horsepower-hour is 5.4 cents, and at h.p., 6.5 cents. 

 During the motor contests held in Canada in 1909 the cost of 

 fuel per actual horsepower-hour was Ij cents for steam, and 

 2 cents for gasoline engines, at stationary work, and approxi- 

 mately double these figures in plowing. The higher fuel 

 cost in Canada would tend to effect the difference between 

 farm and contest efficiency. 



The data just quoted for the cost of horse feed were aver- 

 ages of the period from 1905 to 1907. In 1910, according to 

 the United States Crop Reporter, the price of grain is about 

 25 per cent, above the average of those three years, and that 

 of hay approximately equal. The costs shown for fuel were 

 taken at Winnipeg, in July, 1909, and would be no higher at 

 present prices. In Montana, grain is about 50 per cent., 

 and hay 100 per cent., higher than in Minnesota, while the 

 cost of liquid fuel is also considerably advanced. Varying 

 character and prices of both fuel and food affect the relative 

 commercial efficiency of animal and mechanical motors in 

 different sections, but in general farm practice the horse is 

 less economical in the production of work from latent energy 

 than the tractor, on either the technical or commercial basis. 



