ON HUNGER AND THIRST 451 



to our organic needs, which it is intended to satisfy. The 

 feeling or sensation of thirst in the human subject, when 

 localised, is, in its first or earlier stages, experienced, 

 broadly speaking, in the fauces, and in its second, or 

 later stages, in the whole glosso-pharyngeal area the 

 feeling or sensation itself beginning with slight drying of 

 the natural moisture of the affected mucous surfaces, this 

 drying, as the thirst increases, assuming the proportions 

 of complete inspissation of all intra-oral and pharyngeal 

 moisture, and the closure of every gland exit in the 

 combined cavity of the mouth and pharynx. Why is 

 this feeling or sensation of thirst confined to this anatomi- 

 cal area ? And can there be anatomical reasons for it r 

 To the latter question we simply answer " yes." To 

 the former we shall essay to give our answer in some 

 detail. The region, or regions, affected by thirst, as thus 

 described, coincide exactly with the areas through which 

 escape the secretions of the pituitary body and the 

 salivary glands, and, therefore, compose, or cover, the 

 scene of the first stage of the prolonged process of pan- 

 intestinal digestion. The necessity for the continuous 

 presence of moisture here, or, in its absence, thirst, there- 

 fore, becomes intelligible when we realise that the escape 

 of pituitary matter is only possible in the presence of a 

 liquefying agent, such as saliva, and that the patency of 

 the pituitary canals, and the lacunal inter-spaces of the 

 tonsillo-glossal area through which it escapes, can only be 

 maintained by the existence of open exits, providing for 

 the free discharge of intra-cephalic debris after it has 

 passed through the pituitary body this necessity becom- 

 ing of no less than vital importance when the effete 

 products of brain waste, as they enter the third ventricle, 

 cannot find an escape by the central organs of cephalic 

 drainage and cerebral hygiene, and when, accumulating, 

 they inundate the related cerebral intra-spaces, and com- 

 municating cerebral extra-spaces, to the physical detri- 

 ment and functional disturbance of the whole systemic 

 nervature. 



The feeling or sensation of thirst may thus be said to 

 arise from the curtailment of the freedom of excretory 

 circulation from the central areas of the brain, and 



