SECT. VI. 2. FIBROUS CONTRACTIONS. 37 



deliberate locomotions of the body, and the ideas 

 of recolleftion, as when we will to repeat the alpha- 

 bet backwards. 



4. But as many of thefe fibrous contractions fre- 

 quently accompanied other fibrous contractions, by 

 habit they became caufable by their affociations 

 with them; and the irritations, fenfations, and vo- 

 lition, ceafed to be neceffary to their production. 

 As the actions of the mufcles of the lower limbs in 

 fencing are affociated with thofe of the arms ; and 

 the ideas of fuggeftion are affociated with other 

 ideas, which precede or accompany them ; as in re- 

 peating carelefsly the alphabet in its ufual order af- 

 ter having began it. 



II. We fhall give the following names to thefe 

 four claffes of fibrous motions, and fubjoin their 

 definitions. 



1. Irritative motions. That exertion or change 

 of the fenforium, which is caufed by the appulfes of 

 external bodies, either fimpiy fubfides, or is fuc- 

 ceeded by fenfation, or it produces fibrous motions ; 

 it is termed irritation, and irritative motions are 

 thofe contractions of the mufcular fibres, or of the 

 organs of fenfe, that are immediately confequent 

 to this exertion or change of the fenforium. 



2. Senfitive motions. That exertion or change 

 of the fenforium, which conftitutes pleafure or 

 pain, either fimpiy fubfides, or is fucceeded by vo- 

 lition, or it produces fibrous motions ; it is termed 

 fenfation, and the fenfitive motions are thofe con- 

 tractions of the mufcular fibres, or of the organs 

 of fenfe, that are immediately confequent to this 

 exertion or change of the fenforium. 



3. Voluntary motions. That exertion or change 

 of the fenforium, which conftitutes defire or aver- 

 fion, either fimpiy fubfides, or is fucceeded by 

 fibrous motions \ it is then termed volition, and vo- 

 luntary 



