DISEASES OF VOLITION. SECT.XX^XIY. * 



of age, or of unacquired debility. And the account 

 given before of d replies, which very frequently are 

 owing to a paralyfis of the abforbent fyftem, and 

 are generally attendant on free drinkers of fpiritu- 

 ous liquors, confirmed me in this opi-nion. 



The difagreeable irritation of a difeafed liver pro- 

 duces exertions and confequent quiefcenee ; thefe by 

 the accidental concurrence of other caufes of qui- 

 efcence, as cold, folar or lunar periods, inanition, 

 the want of their ufual portion of fpirit of wine> 

 at length produces paralyfis. 



This is further confirmed by obferving, that the 

 x mufcies, we moft frequently, or moll powerfully 

 exert, are mod liable to palfy ; as thofe oi the voice 

 and of articulation, and of thofe paralytics which 

 I have- feen, a much greater proportion have loft 

 the ufe of their right arm; which is fo much more 

 generally exerted than the left. 



I cannot difmifs this fubjefc without obferving y 

 that after a paralytic ftroke, if the vital powers are 

 not much injured, the patient has all the move* 

 mems of the affecled limb to learn over again, jufl 

 as in early infancy ; the limb is firft moved by the 

 irritation of its mufcies, as in flretching, (of which 

 a cafe was related in Sedlion VII. i. 3.) or by the 

 eleftrie concuifion ; a 1 terwards it becomes obedient 

 to fenfation, as in violent danger or fear ; and laftly, 

 the mufcies become again aflociated with volition, 

 and gradually acquire their ufual habits of adliiig 

 together. 



Another phsenomenon in palfies is, that when the 

 limbs of one fide are difabled, thofe of the other 

 are in perpetual motion. This can only be explain- 

 ed from conceiving that the power of motion, what- 

 ever it is, or wherever it refides, and which is ca- 

 pable of being exhaufted by fatigue, and accumu- 

 lated in reft, is now lefs expended, whilfl one half 

 of the body is capable of receiving its due propor- 



tion 



