CHRONIC BRIGHT'S DISEASE. 23 



phenomenon of far greater importance. The significance of this cir- 

 cumstance consists in the fact that, as long as the dropsy keeps in- 

 creasing, the saline contents of the urine are very small, but whenever 

 any rapid diminution of the effusion takes place, the salts are elimi- 

 nated into the urine more freely, much more freely, indeed, than under 

 normal conditions. 



If a portion of the urine be heated, after addition of a few drops 

 of acetic acid, in case its reaction should be alkaline, or if nitric acid 

 be added, the albumen coagulates. According to Frerichs, its quan- 

 tity ranges from about 2.5 to 15.0 p. M. This presence of albuminuria, 

 which usually persists throughout the whole course of the disease, and 

 only disappears now and then, for short periods, unfortunately cannot 

 be satisfactorily accounted for. One might be led into mistaking the 

 albumen and the exudation cylinders for the products of inflammation, 

 excreted from the free surface of the tubules, were it not that, in other 

 and non-inflammatory diseases of the kidney, the urine contains both 

 tube-casts 'and large amounts of albumen. I believe the presence of 

 albumen in the urine to depend upon the destruction or degeneration 

 of the epithelium. That normal urine should not contain albumen is 

 confessedly extremely perplexing to the physiologists. They are al- 

 most forced to suppose that the albumen does transude into the kidney, 

 together with the water and salts ; and they are reduced to the hy- 

 pothesis that its absence from normal urine is in some way connected 

 with the epithelial lining of the uriniferous tubules, the transuded 

 albumen either becoming assimilated for the nutrition of the epithe- 

 lium, or else its diffusion into the tubules, receiving some other modifi- 

 cation, as yet unknown to us, from the epithelium. The observation 

 that albuminuria exists in all diseases of the kidney, in which its epi- 

 thelium is either degenerated cr destroyed, fully confirms this physio- 

 logical hypothesis. 



After the urine has been allowed to stand for a while, a light, 

 whitish, flocculent precipitate falls to the bottom of the vessel. If this 

 sediment be placed under the microscope (for this purpose it is best to 

 let it deposit in the bottom of a pointed champagne-glass), the well- 

 known casts are found. At the commencement of the disease they 

 are covered by epithelium, in a state of fatty metamorphosis ; at a later 

 period, they seem quite bare, or are merely covered with granules and 

 globules of fat. Besides this, the sediment contains common epithe- 

 lial cells from the urinary passages, and smaller round, slightly-gran- 

 ular cells. 



[By many the so-called urinary cylinders are supposed to be a 

 product of the blood ; others ascribe their origin to alteration of 

 the epithelium. They probably originate in various ways. The 

 52 



