230 DRAUGHT AND HARNESS. 



known advantage of applying force as near as possible 

 to the centre of gravity of the object to be moved 

 depends to so great an extent on the possibility thereby 

 acquired of avoiding waste of power by the force being 

 exerted at a wrong angle or in a wrong direction, that 

 this consideration (the angle or the direction) becomes 

 the principal one. 



It is indeed well known to artillery officers that a 

 considerably greater weight per horse may be calculated 

 on for teams of four than for those composed of six, 

 eight, or twelve horses ; but this does not depend on 

 the greater distance of the leaders from the carriage, 

 but on the difficulty of getting the increased number of 

 horses to act simultaneously and in the proper direction 

 in proof of which may be mentioned the fact that 

 it is well understood that no real advantage can be 

 attained by harnessing more than ten horses to one 

 carriage, however these may be disposed, and at what 

 distances. It is, then, the angle under which the effort 

 is exercised, much more than the distance of the motor 

 from the load, that requires study and consideration. 

 For instance, no one ever thinks of using in the traction 

 of canal-boats a towing-rope only just long enough to 

 reach the bank. On the contrary, it may be advan- 

 tageously lengthened till it forms a very small angle with 

 the keel-line of the boat, otherwise there will be great 

 waste of power through the action of the rudder. No- 

 doubt the weight of the longer rope must be also taken 

 into consideration ; but what an enormous difference 

 there is between the length of a towing-rope and that 

 of an ordinary carriage -trace, and still people will haggle 

 about inches in the latter. In like manner, in carriage 

 draught the inclination of the traces to the longitudinal 



