6 



EXPERIMENT STATION RECORD, 



values are naturally still further in('r(>as('<l duriuo- the military maneu- 

 vers. Poncelet's liuures are almost the same as Ellenl)erger\s. 



In order to determine the distance traveled, the data furnished by 

 Colin are used. A saddle horse walking a kilometer in 10 minutes 

 travels at a speed of 1.66 meters per second. Trotting a kilometer in 

 ■li minutes, an average speed in the opinion of cavalry officers, he 

 travels 3.02 meters per second. Colin found that the average speed 

 of a trotting horse was 2.72 meters per second. The first value must 

 refer to a full gallop, and the latter value seems to be a fairer estimate. 

 Using this and following Poncelet's method, the amount of work per- 

 formed l)y a horse in a day is expressed by the following formula: 

 P X V X T = PVT kilogrammeters, in which V = mean velocity in 

 meters, P = mean exertion in kilograms, and T = time. Of course 

 these values necessarily have limits. Thus the limit for T is estimated 

 by Poncelet at 18 hours; that for P, 3 to 5 times that which produces 

 a maximum of etfectiveness, and V at 12 to 15 times the velocity best 

 suited to the production of work with the horse under consideration. 

 These values are worth noting, but can not be accepted as final, and 

 there is much disagreement concerning the proper values. It is, how- 

 ever, generally admitted that T is diminished in proportion as P X V 

 is increased. Race horses furnish a striking illustration of this. 

 Applying the above values to the arm}^ horse, which travels more 

 regularly than the others, and assuming that the average rider weighs 

 approximate!}^ 80 kg. without a pack and weighs 120 kg. with, the 

 calculated amount of work performed would be as follows: 



Work performed daily by an army horse. 



Weight 

 carried. 



Velocity 



per 

 second. 



Work 

 per sec- 

 ond. 



Sdr'«f^-°^kat 

 work different 

 ^^^'^- gaits. 



Total daily 

 work. 



Ordinary work: 



Walking , 



Trotting 



Road work: 



Walking 



Trotting 



Military maneuvers 



Walking , 



Trotting 



A7/. 



T20 

 120 



Meters. 

 1.66 

 2.75 



1.66 

 2.75 



1.66 

 2.75 



Kgm. 

 132.8 

 216. 



199.2 

 322. 



149.4 

 247.5 



Hrs. Mill. 

 2 30 

 1 30 



Kgm. 

 1, 195, 200 

 1, 166, 400 



1,074,000 

 1,792,800 



1,072,800 

 2, 667, 600 



Kgm. 

 2,361,000 



807,400 



I 3,740,^ 



It will be seen that using Poncelet's formula we do not obtain his 

 values, namely, 4.752,000 kilogrammeters for a horse walking 10 

 hours, carrying a load of 120 kg., and ■1,435,000 kilogrammeters for a 

 horse carrying a load of 80 kg. and trotting 7 hours. 



The values noted above undoubtedly show something of the labor 

 expended, but are far less exact than results o])tained with a dyna- 

 mometer. With artillery horses and those in the train, the prol)lem 

 becomes much more complicated, since these horses draw a load and 



