GENERAL SENSATIONS. 387 



opinion as to the seat of hunger is, perhaps, only in our 

 knowledge of the fact that this sensation ceases when food is 

 introduced into the stomach. 1 The case is the same in 

 regard to thirst: the sensation of dryness of the throat is 

 caused by a diminution of secretion in these parts, as well as 

 throughout the organism, in most cases this dryness being 

 accompanied by a diminution of the sweat and urine. The 

 sensations accompanying satiety are also purely general, being 

 sometimes agreeable and sometimes disagreeable, and having, 

 properly speaking, no fixed seat : indeed, hunger and thirst 

 are sometimes experienced in the highest degree, especially 

 in pathological cases, and in cases of non-absorption, in spite 

 of the ingestion of large quantities of food and drink. 



The sensations belonging to the other extremity of the 

 digestive tract are more distinct : that, for instance, known 

 as the desire for defecation, the seat of which is not, however, 

 easily defined. It is generally supposed to be situated in the 

 rectum, but it seems more likely to belong to the intestinal 

 tube, as shown by cases of abnormal anus (see p. 278). This 

 sensation indicates simply that the rectum is ready to evac- 

 uate the substances with which it is filled. The defecation 

 which follows is an entirely reflex phenomenon, which we 

 have already studied at length. The agreeable sensation 

 which follows defecation is caused by the overcoming of 

 a difficulty; in place of this, however, in cases of irrita- 

 tion of the intestine or rectum, a peculiar and painful 

 sensation is sometimes experienced, known under the name 

 of tenesmus, producing a desire to throw off the fecal 

 matters even when the intestine is completely empty. 



A foreign body produces scarcely any distinct sensation 

 in the mucous of the pulmonary organs: its hardness, its 

 form, and its temperature, are felt very slightly if at all ; it, 

 however, produces a vague sensation of pain and uneasiness, 

 and immediately causes a reflex action, giving rise to an in- 

 voluntary cough, for the purpose of expelling the offending 



1 ' ' I have questioned a number of soldiers on this point, choosing 

 carefully those who were ignorant of anatomy, in order that their 

 replies might not be influenced by any involuntary localizing of the 

 sensation. Several among them vaguely indicated the neck or the 

 chest as the seat of hunger, twenty-three indicated the sternum, 

 four could not trace the sensation to any particular spot, while two 

 only designated the stomach. These latter were hospital nurses, 

 and had, consequently, a few ideas in regard to anatomy." Schiif, 

 " Physiologic de la Digestion." 



