"ECT. XI. 2. SENSOKIAL ACTIONS. 57 



frequently continues fome time after the ideas or 

 mufcular motions which excited it have ceafed: 

 for we often feel a glow of pleafure from an agree- 

 able reverie, for many minutes after the ideas, that 

 were the fubject of it, have efcaped our memory ; 

 and frequently experience a dejectiotyof fpirits with- 

 out being able to ailign the caufe of it but by much 

 recolleclion. 



When the fenforial faculty of defire or averfion 

 is exerted fo as to caufe fibrous motions, it is term- 

 ed volition ; which is faid in Seel. V. to be a mo- 

 tion of the central parts, or of the whole fenforium, 

 terminating in fome of the extremities of it. This 

 appears, firft, becaufe our defires and averfions al- 

 ways terminate in recollecting and comparing our 

 ideas, or in exerting our mufcles ; which are the 

 motions of the extremities of the fenforium And, 

 fecondly, becaufe defire or averfion begins, and 

 frequently continues for a time in the central parts 

 of the fenforium, before it is peculiarly exerted at 

 the extremities of it ; for we fometimes feel defire 

 or averfion without immediately knowing their 

 objects, and in confequence without immediately 

 exerting any of our mufcular or fenfual motions to 

 attain them : as in the beginning of the paflion of 

 love, and perhaps of hunger, or in the ennui of 

 indolent people. 



Though ienfation and volition begin or termi- 

 nate at the extremities or central parts of the fen- 

 forium, yet the whole of it is frequently influenced 

 by the exertion of thefe faculties, as appears from 

 their effects on the external habit : for the whole 

 fkin is reddened by mame, and an univeral tremb- 

 ling is produced by fear : and every mufcle of the 

 body is agitated in angry people by the defire of 

 revenge. 



There is another ver ycurious circumftance, which 

 {hews that fenfation and volition are movements of 



the 



