226 CATENATION OF MOT IONS. SECT, xvrl 2. 



reftored. Thus in the common impediment of 

 fpeech, when the aflbciation of the motions of the 

 mufcles of enunciation with the idea of the word 

 to be fpoken is difordered, the great voluntary ef- 

 forts, which diftort the countenance, prevent the 

 rejoining of the broken aflbciations. See No. II. 

 ip. of this Section. It is thus likewife obfervable 

 in fome inflammations of the bowels, the too flrong 

 efforts made by the mufcles to carry forward the 

 offending material fixes it more firmly in its place, 

 and prevents the cure. So in endeavouring to re- 

 cal to our memory fome particular word of a fen- 

 tence, if we exert ourfelves too ftrongly about it, 

 we are lefs likely to regain it. 



1 1 . Catenated trains or tribes of action are eafier 

 diflevered than catenated circles of action. Hence 

 in epileptic fits the fynchronous connected tribes of 

 action, which keep the body erect, are diffevered, 

 but the circle of vital motions continues undifturb- 

 cd. 



12. Sleep deitroys the power of volition, and 

 precludes the flimuli of external objects, and thence 

 difievers the trains, of which thefe are a part; 

 which confirms the other catenations, as thofe of 

 the vital motions, fecretions, and abforptions ; and 

 produces the new trains of ideas, which constitute 

 our dreams. 



II. i. All the preceding circumflances of the 

 catenations of animal motions will be more clearly 

 underftood by the following example of a perfon 

 learning mufic ; and when we recollect the variety 

 of mechanic arts, which are performed by aflbciated 

 trains of mufcular actions catenated with the effects 

 they produce, as in knitting, netting, weaving ; 

 and the greater variety of affociated trains of ideas 

 caufed or catenated by volitions or fenfations, as in 



our 



