64 



The experiments which have had to do with the rations best suited 

 for horses emplo3^ed at different kinds of work are obviously attempts 

 to suit the food to the amount of work performed. 



Lavalard'^' calculated the amount of food required by army horses 

 and mules to maintain weight on a peace and war footing- as follows, 

 the amount of work in the latter case being more than in the former. 



Table 8. — Calculated ration of French army horses and mules. 



Cavalry horses, reserve 



Cavalry horses, line 



Light cavalry horses 



Horses of artillery and train 

 Mules 



Peace footing. 



Oats. 



Pounds. 

 13 



11.5 

 10.4 

 12.3 

 10.8 



Hay. 



Pounds. 



8.8 

 7. 7 

 6.6 

 8.5 

 7.5 



War footing. 



Oats. 



Pormds. 

 U.I 

 13.5 

 11.8 

 14.2 



Hay. 



Pounds. 

 8.8 

 7.7 

 6.6 

 8.6 



Similar calculations, which have been made by others, have been 

 summarized in Tal)le 5, page 49. 



Grandeau's experiments* have shown the marked effect of pace on 

 the amount of labor performed and food required. He showed that a 

 horse walking 7.8 kilometers (5.8 miles) per day neither gained nor 

 lost in weight on a daih^ ration of 8,800 grams (40 pounds) of hay, 

 while a ration of lu,886 grams (49.5 pounds) was not sufficient, pro- 

 vided the horse trotted the same distance. When the horse walked 

 tlie above distance and drew a load, the additional work being equiva- 

 lent to 60,449 kilogrammeters (437,080 foot-pounds), a ration of 11,975 

 grams (!^6.4 pounds) of hay was sufficient for maintenance. A ration 

 of 14,787 grams (32.6 pounds), all a horse would consume, was not 

 sufficient for maintenance when the same work was done trotting. 



According to Grandeau* a horse of 500 kilograms (1,100 pounds) 

 weight by the motion of forward progression through a horizontal 

 distance of 10 kilometers (6.2 miles) at a speed of 1.5 meters (4,9 feet) 

 per second loses 2.4 kilograms (5.3 pounds) in weight. A horse of the 

 same weight covering a distance of 10 kilometers (6.2 miles) at a speed 

 of 1.5 meters (4.9 feet) per second and producing 190,000 kilograms 

 of work loses about 3.8 kilograms {SA pounds) in weight. Some of 

 the reasons given for the fact that rapid Avork is less economical than 

 slow work are the increased action of the heart when the horse is trot- 

 ting or galloping; the lifting of his own weight at each step only to 

 allow it to fall again, thus developing heat; and the increase of bodj^ 

 temperature with exertion and the loss of heat bj^ the evaporation of water 

 through the skin and lungs. Grandeau determined the average amount 

 of water thus evaporated under different conditions of work and rest 

 with four different rations, the distance covered in every case being the 



"Loc. cit. 



^ See note, p. 66. 



