140 THE MECHANICAL FUNCTIONS. 



ployed for the larger movements, and another set 

 provided for the accurate regulation of the more 

 delicate intlcxions and nicer positions. This we 

 shall find exemi)litied in the movements of the 

 lingers, and of many of the organs of the finer 

 senses. 



In general, however, we may observe that the 

 mechanical expedients devised by Nature for 

 eft'ecling each particular purpose are charac- 

 terised by the most admirable simplicity. In 

 this respect, also, as well as in all others, we 

 cannot fail to recognise their infinite superiority 

 over every corresponding invention of man. 



" J 11 liuman works, tliough laboiir'd oii with pain, 

 A tljousand movements scarce one purpose gain ; 

 In God's, one single can its ends produce, 

 Yet serves to second too some other use." Pope. 



We may generally observe, in the mechanism 

 of the joints, ihat the muscles are made to act, 

 cither directly or by means of their tendons, at a 

 point much nearer to the axis of motion than 

 the resistance to be overcome. Witli regard to 

 the direct force, therefore, it is evident that 

 they nmst act with a great mechanical disad- 

 vantage ; and this disadvantage is stUl farther 

 increased by the obliquity of the action with re- 

 ference to the direction of the motion. But the 

 contractile power, which is inherent in the mus- 

 cular fibre, is so enormous, as amply to aflbrd 



