120 MECHANISM OF THE MUSCLES. 



any particular part, as that of the porter in the back ; 

 the sailor in the hands and arras, &c. ; the strength 

 necessary is made to arise from the very exertions 

 which requires it. The necessity furnishes its own 

 supply. 



B. This is as though the sailor were to change 

 a small rope into a cable, merely by fastening on an 

 anchor. Creative power alone can accomplish such 

 wonders. 



T. The subject is of so much concern to us in 

 many respects, that it is important the principle 

 should be remembered. Do you recollect Dr. Bell's 

 observations in his Animal Mechanics ? 



A. " Exercise, " he remarks, " unfolds fully the 

 muscular system, producing a full, bold outline of the 

 limbs, at the same time that the joints are knit, small 

 and clean. In the loins, thighs and legs of a dancer, 

 we see the muscular system fully developed, and 

 when we turn our attention to his puny and dispro- 

 portioned arms, we acknowledge the cause, that in 

 the one instance, exercise has produced perfection, 

 and that in the other, the want of it, has occasioned 

 deformity. Look to the legs of a poor Irishman, 

 travelling to the harvest with bear feet ; the thick- 

 ness and roundness of the calf show that the foot 

 and toes are free to prevent the exercise of the mus- 

 cles of the leg. Look, again, to the leg of an En- 

 glish peasant, whose foot and ankle are tightly laced 

 in a shoe with a wooden sole, and you will perceive 

 from the manner in which he lifts his legs, that the 

 play of the ankle, foot, and toes, is lost as much as if 



