THE MICROSCOPE IN DIAGNOSIS. 307 



comes grayish or blackish from the formation of the sub- 

 oxide or of metallic bismuth. 



URINARY DEPOSITS. 



Deposits from urine are either organic or precipitates 

 from solution. The urine should be put in a conical glass 

 of four or five ounces capacity, and kept free from dust 

 for about twelve hours. A small portion of the sediment 

 should then be taken up with a clean pipette and ex- 

 amined under the microscope on a glass slide covered in 

 the usual way (page 77). A quarter of an inch objective 

 will be found most generally useful. 



To facilitate microscopical examination and diagnosis 

 we add the following table from Richardson's Medical 

 Jli'-roscopy : 



I. A distinct deposit is seen in the urine. 



A. This deposit is light and flocculent. 



a. It occurs in albuminous urine, one yielding a coagu- 

 lum with heat and nitric acid. 



a. The microscope shows casts of the uriniferous tubules 

 (transparent or granular cylinders s'^th to y^-^th of an 

 inch in diameter), either granular, epithelial, or hyaline, 

 Bright's disease of the kidney. 



,?. The microscope shows red blood-corpuscles (non-nu- 

 cleated disks gsVoth of an inch in diameter), mixed with 

 mucus, hcematuria. 



Y. Leucocytes only are seen (nucleated corpuscles, pus- 

 corpuscles, o^o^th of an inch in diameter), nephritis, 

 cystitis, etc. 



b. The urine is not albuminous. 



a. Leucocytes, epithelial cells from the bladder, and per- 

 haps mucous casts of the tubules appear, irritation of 

 urinary tract. 



,''. Spermatozoa, if numerous, spermatorrhoea. 



r- Fungous growths (cellular bodies j^th to 



