ON MUSCULAR ACTION, 101 



cation, has rendered the combination of powers 

 easy and certain. Not to mention the more obvious 

 and graceful movements of dancing, fencing, and 

 riding, we discover, in the management of the hand 

 and fingers by engravers, sculptors, watchmakers, 

 jugglers, and other artists and mechanics, a minute 

 accuracy of muscular adjustment to effect a given 

 end, which is the more surprising the more we 

 consider the complicated means by which it is 

 effected. 



In consequence of the co-operation of both nerve 

 and muscular fibre being required to effect motion, 

 excess of action in each is followed by results pecu- 

 liar to -itself. If the NERVES preponderate, either 

 constitutionally or from over-exercise, as they are 

 apt to do in highly nervous temperaments, their 

 excessive irritability renders them liable to be un- 

 duly excited by ordinary stimuli ; and hence, as in 

 hysteric and nervous females, a proneness to sudden 

 starts, cramps, and convulsions, from causes which 

 would scarcely affect an individual differently con- 

 stituted. Such persons have little muscular power, 

 except under excitement ; they then become capable 

 of great efforts, of short duration, but sink propor- 

 tionally low when the stimulus is past. If, on the 

 other hand, the MUSCLES predominate, as in athletic 

 strong-built men, the nervous system is generally 

 dull and little susceptible of excitement, and the 

 muscles which it animates are consequently little 

 prone to the rapid and vivacious action which ac- 

 companies the predominance of the nervous func 

 tions. Great strength and capability of bodily labour 

 are then the characteristics. 



Great muscular power and intense nervous action 

 are rarely conjoined in the same individual ; but 

 when they do happen to meet, they constitute a per- 

 fect genius for muscular exertion, and enable their 

 possessor to perform feats of strength and agility 

 which appear marvellous to those who are deficient 

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