Class III. 1. 1. 8. OF VOLITION. 287 



verie or fomnambulation. About half an hour before the ex- 

 pected return of the fit three or four grains of opium were ex- 

 hibited, and then tincture of opium was given in warm brandy 

 and water about twenty or thirty drops every half hour, till the 

 eyes became fomewhat inflamed, and the nofe began to itch, 

 and by the (harp movements of the patient, or quick fpeech, an 

 evident intoxication appeared ; and then it generally happened 

 that the pain ceafed. But the effects of this large dofe of opium 

 was fueeeeded by perpetual ficknefs and efforts to vomit, with 

 great general debility all the fucceeding day. 



The rationale of this temporary cure from the exhibition of 

 opium and vinous fpirit depends on the great expenditure of 

 fenforial power in the increased actions of ail the irritative men- 

 tions, by the flimulus of fuch large quantities rjf opium and vi- 

 nous fpirit ; together with the production of much fenfation, 

 and many movements of the organs of fenfe or ideas in confe- 

 qu~nce of that fenfation •, and laftly, even the motions of the 

 arterial fyftern become accelerated by this degree of intoxica- 

 tion, all which foon exhaufted fo much fenforial power as to re- 

 lieve the pain j which would otherwife have caufed convulfions 

 or infanity, which are other means of expending fenforial pow- 

 er. The general debility on the fucceeding day, and the partic- 

 ular debility of the flomach, attended in confequence with fick- 

 nefs and frequent efforts to vomit, were occafioned by the fyf- 

 tern having previoufly been fo ftrongly ftimulated, and thofe 

 parts in particular on which the opium and wine more imme- 

 diately acted. This ficknefs continued fo many hours as to 

 break the catenation of motions, which had daily reproduced 

 the paroxyfm ; and thus it generally happened, that the whole 

 difeafe ceafed for fome weeks or months from one great intoxi- 

 cation, a circumftance not eafily to be explained on any other 

 theory. 



The excefs or defect of motion in any part of the fyftern oc- 

 cations the production of pain in that part, as in Sect. XII. 1. 6. 

 This defect or excefs of fibrous action is generally induced by 

 excefs or defect of the flimulus of objects external to the mov- 

 ing organ. But there is another fource of exceflive fibrous ac- 

 tion, and confequent pain, which is from excefs of volition, 

 which is liable to affect thofe mufcles, that have weak antago- 

 nifts ; as thofe which fupport the under jaw, and clofe the mouth 

 in biting, and thofe of the calf of the leg ; which are thus liable 

 to fixed ©r painful contractions, as in trifmus, or locked jaw, and 

 in the cramp cf the calf of the leg ; and perhaps in feme colics, 

 as in that of Japan : thele pains, from contraction arifing from 

 excels of volition in the pan from the want of the counteraction 



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