THE MICROSCOPE. 165 



frequently accompanied by and entangled with the small casts of the 

 uriniferous tubes, while the blood particles which come from the 

 bladder are mixed with more or less vesical epithelium, which is flat 

 and scaly, and readily distinguished from that of the kidneys. But 

 this, to be of any value in differential diagnosis, must be supple- 

 mented by a careful observation of all the symptoms, local and con- 

 stitutional, connected with the urinary derangement, as well as a 

 careful examination of all foreign matter found with the blood and 

 all its characteristics. The blood corpuscles which we detect with 

 the microscope are not always of uniform appearance, and are never 

 seen to collect in rouleaux. 



Another substance most readily discovered by the aid of the 

 microscope is fat, but in this it is well to confirm our discovery by the 

 means which chemistry so readily affords. Here we must guard 

 very carefully against errors, whether the fat denotes such a degene- 

 ration, or is chylous, or in free globules, or associated with albumin- 

 uria and tube casts, and attended by dropsy, or whether it comes 

 from the ingestion of such articles as contain fat in large quantities. 

 Fat may continue in the urine in free cells without albumin for 

 years, and not denote disease of the kidney. 



Another substance of much interest to the microscopist and 

 diagnostician, is pus as found in the sediment of the urine. Dr. 

 Fell, in a paper read before the Medical and Surgical Society of 

 Buffalo, last September, said: "With the microscope the pus cor- 

 puscle is readily recognized, and this use of the instrument is alone 

 so far-reaching in its value as to warrant the statement that it alone 

 furnishes sufficient reason for the teaching of microscopical tech- 

 nology in every medical college throughout the land." Though the 

 pus corpuscle may sometimes be indistinct, and become a source of 

 error when the urine, on being voided, is strongly ammoniacal, by 

 being confounded with that of the mucous corpuscle, heat and nitric 

 acid make a ready test; for where pus is found albumin is also 

 present, but with the mucus corpuscle albumin is never associatedi 

 although entangling quantities of epithelium cells, thus adding 

 microscopical evidence. The localization of the source of the pus 

 is, by close study, much enlightened, for the corpuscles from the 

 kidney are irregular in contour and nuclei, and with partially 

 destroyed cells. The corpuscles of the bladder are regular. 



"The presence of albumin in the urine is considered by the ma- 



