CROUPOUS PNEUMONIA. 175 



at all of an irritable temperament, there is apt to be slight delirium. 

 These symptoms are mainly due to the fever, and cease as soon as the 

 fever subsides. We must beware of inferring the existence of grave 

 cerebral disease from the presence of these signs alone. 



Even where there is no complicating gastric disorder, the appetite 

 usually is lost, the tongue is lightly coated with white, and shows a 

 tendency to dryness, the thirst is considerably augmented, and the 

 stools are dry and constipated. These symptoms are also the result of 

 fever, and occur in almost every other febrile complaint. The loss of 

 appetite is the most difficult to account for. One would suppose, a 

 priori^ that the augmented destructive assimilation which takes place 

 during fever, by means of which the high temperature of the body is 

 maintained, would occasion an increased demand on the part of the 

 system for a compensating supply of nourishment to replace the waste, 

 and we are quite at a loss to understand why no such want is usually 

 felt by the patient. The coated tongue, its tendency to dryness, as well 

 as the aggravated thirst (see catarrh pf the oral mucous membrane), 

 and the dryness of the stools, are satisfactorily accounted for by the in- 

 creased evaporation of liquid from the skin, in consequence of which 

 the tissues become dryer and then* secretion is diminished. 



Obstruction to the flow of blood from the liver not unfrequeiitly 

 leads to a perceptible enlargement of that organ. Perhaps, in some 

 oases, the slight jaundice which occurs during pneumonia is dependent 

 upon this obstruction of circulation in the liver, and is analogous to the 

 icterus which appears, from the same cause, with tolerable frequence in 

 disease of the heart. As the hepatic veins are intertwined with the 

 biliary ducts, distention of the former may result in compression of the 

 latter, and thus cause retention and absorption of bile. However, this- 

 theory of the origin of icterus is only to be admitted when the liver is 

 greatly swelled and the patient is extremely cyanotic. Far more fre- 

 quently, the symptoms of jaundice during pneumonia depend upon a 

 catarrh of the duodenum and of the biliary ducts, or else it arises from 

 " dissolution " of the blood that is to say, a disintegration of the blood- 

 corpuscles, by which free coloring-matter of the blood is converted into 

 biliary coloring-matter outside of the liver. 



The pneumonic process and the fever which attends it exercise an 

 important influence upon the constitution of the urine. While the fever 

 lasts the proportion of water in the urine is reduced by the insensible 

 perspiration. The urine is scanty and concentrated, its color is some 

 what dark, and its specific gravity is high. 



Among the solid constituents of the urine, the urea is considerably 

 increased in quantity. As is well known, the ultimate products of de- 

 structive assimilation of nitrogenous tissues are eliminated under the form 



