ON DRAUGHT. 



537 



while considering the best and most advantageous application of this power 

 and we must be excused the frequent repetition of the terms, for the sake of the 

 clearness gained by it it would appear that the resistance should be as much 

 as possible rigid and inelastic, so as to receive immediately, and unimpaired, the 

 direct effects of the slightly irregular exertions of the animal ; that this resist- 

 ance should not be such as to yield directly to a sudden impulse ; that it should 

 be so far uniform as to be free from violent changes or sudden shocks, but not 

 so constant as to allow of no remission, nor of those alternations of exertion 

 and comparative relaxation which we have stated to be advantageous to the 

 perfect development of animal power. 



Fig. 14. Fig. 15. 



That, as regards the degree of resistance, where velocity is not required, a 

 force of traction of from lOOlbs. to 12olbs., or even ISOlbs.*, according to the 

 strength of the horse, continued for eight hours a day, at about two and a half 

 to three miles per hour, is the best proportion of quantity and duration of 

 labour ; that where six or eight miles per hour is required, the duration of the 

 day's work should be shortened to five or six hours, and the draught reduced to 

 SOlbs. or lOOlbs. At still higher velocities the draught must not exceed SOlbs. 

 or 60lbs., and the time of working two or three hours. But this speed can only 

 be attained by the sacrifice of the horse ; and consequently the question will 

 rather be what the horse is capable of doing than what can be done with 

 economy ; and it becomes a matter of calculation depending altogether upon the 

 first cost of the horse, and the profits arising from his employment. 



With respect to the mode of harnessing the horse, it is hardly necessary to 

 say that great care should be taken in fitting the collar and in attaching the 

 traces to the proper point. As to the direction of the traces, it must, as we 

 have shown, entirely depend upon the circumstances of the case. Where the 

 draught is heavy and slow, if the road be good, the traces should be nearly 



" The load winch will produce this amount of draught will be determined when we con- 

 eider the subject of the roads, on the quality of which it will be seen that this mainly depends. 



