CLASS I. 2. 4. i. OF IRRITATION. loj 



the glans penis. If its ftimulus be greater, it then induces pain 

 at the neck of the bladder. The concretions of bile, which are 

 protruded into the neck of the gall-bladder, when the difeafe is 

 not very great, produce pain at the other extremity of the bile- 

 duel:, which enters the duodenum immediately under the pit of 

 the ftomach ; but, when the difeafe is great -from the largenefs 

 of the bile-ftone, the pain is felt in the region of the liver ac the 

 neck of the gall-bladder. 



It appears from herrce,* that the psircs enumerated in this ge- 

 nus are confequences of the inactivity of the organ , and, as they 

 do not occaiion other difeafes, ihould be claffed according to 

 their proximate caufe, which is, defective irritation ; there are 

 neverthelefs other pains from defect of ftimulus, which produce 

 convulfions, and belong to Clafs III. i. I. ; and others, which 

 produce pains of fome diftant part by aflbciacion, and belong to 

 Clafs IV. 2. 2. 



SPECIES. 



I. Sitif. Thirft. The fenfes of thirft and of hunger feeni 

 to have this connexion, that the former is fituated at the upper 

 end, and the latter at the lower end of the fame canal. One 

 about the pharinx, where the cefophagus opens into the mouth, 

 and the other about the cardia ventriculi, where it opens into the 

 ftomach. The extremities of other canals have been (hewn to 

 poflefs correfpondent fenfibilities, or irritabilities, as the two ends 

 of the urethra, and of the common gall-duet. See IV. 2. 2. 2. 

 and 4. 



The membrane of the upper end of the gullet becomes torpid, 

 and confequently painful, when there is a deficiency of aqueous 

 3uid in the general fyftem ; it then wants its proper ftimulus. 

 In the fame manner a want of the ftimulus of more folid mate- 

 rials at the other end of the canal, which terminates in the ftom- 

 ach, produces hunger ; as mentioned in Seet. XIV. 8. The 

 proximate caufes of both of them therefore confift in deficient 

 irritation, when they are confidered as pains , becaufe thefe pains 

 are in confcquence of t-he inactivity of the organ, according to 

 the fifth law of animal caufation. Seel:. IV. 5. But when they 

 are confidered as defires, namely, of liquid or folid aliment, 

 their proximate caufe confifts in the pain of them, according to 

 the fixth law of animal caufation. So the proximate caufe of 

 the pain of coldnefs is the inactivity of the organ, and perhaps 

 the confequent accumulation of fenforial power in it ; but the 

 pain itfelf or the confequent volition, is the proximate caufe of the 



VOL. II. P (huddering 



