208 THE SECRETIONS: 



the blood bears an accurate and inseparable relation to the fever, 

 there can be no doubt that the change in the constitution of 

 the urine must be in relation to the same cause, for the urine 

 is separated from the blood, and was previously an integral con- 

 stituent of it; and because, further, every alteration in the con- 

 stitution of the blood must involve corresponding changes in 

 the secretions and excretions, and more especially in the urine. 

 Since like effects follow like causes, and since in inflammatory 

 affections the vascular system similarly participates in the dis- 

 turbance, we may assume a priori that similar changes will 

 occur in the urine, a point confirmed by experience. 



The urine discharged during inflammations is usually termed 

 febrile urine. There is no objection to this term, since the cause 

 of the change in the urine must be sought for in the fever : I 

 shall, however, not introduce the term ' febrile urine' here, since 

 it is more than probable that the changes in the composition 

 of the urine vary according as the character of the fever is 

 synochal or torpid. My analyses show, in fact, that the rela- 

 tive proportions of urea in fevers of a torpid and of a synochal 

 character are different ; and although the analyses are not yet 

 sufficiently numerous to establish the difference with certainty, 

 it still appears to me to be a point of sufficient importance to 

 demand attention, and one that should be carefully worked out. 



In order to take a correct view of the composition of the 

 urine, we must bear in mind the composition of the blood, the 

 reaction of the vascular system, and the diet, since the mixture 

 of the proximate constituents is dependent upon these circum- 

 stances. 



The following are the general characteristics of the urine in 

 inflammatory affections : The urine is darker than usual, and is 

 of a yellow, brown, or reddish-brown tint ; it has an acid reac- 

 tion, and is generally of a high specific gravity. With respect 

 to its most important constituents, the urea is either absolutely 

 increased, or is at the ordinary physiological average, or may 

 be a little below it; the uric acid is always absolutely increased, 

 and so are the extractive matters, especially the alcohol- extract. 

 The salts are always absolutely diminished, especially the chlo- 

 ride of sodium ; the sulphates, on the other hand, either ap- 

 proximate to the physiological average, or are not far below it. 

 Assuming, as the mean of numerous analyses, that the urea 



