THE MICROSCOPE IN PATHOLOGY AND MEDICINE. 235 



liar caudate cell was characteristic of cancer, but constant 

 research has shown that there is no special form of cell 

 in this disease. The greater number of cancers may be 

 characterized as a proliferation and ingrowing of epithe- 

 lial elements, either of the surface or of the glands. Figs. 

 189 to 191, Plate XXY, illustrate several varieties of 

 carcinoma. 



The anomalies of the various tissues and organs are 

 well delineated by Rindfleisch in his Pathological Histology. 



IV. MICROSCOPIC EXAMINATION OF URINARY DEPOSITS. 



Healthy urine holds in solution a variety of organic and 

 inorganic substances, as urea, uric acid, alkaline and earthy 

 salts, animal extractive, vesical mucus, and epithelial de- 

 bris. A few drops allowed to evaporate on a glass slide 

 will exhibit the crystalline matters, consisting of urea, 

 urate of soda, chloride of sodium, phosphates and sul- 

 phates. 



The amount passed each twenty-four hours varies from 

 20 to 50 ounces, holding in solution from 600 to 700 grains 

 of solid matter. Of this, about three-fourths consists of 

 organic, and one-fourth of saline substances, the largest 

 amount being urea, comprising nearly two-thirds of the 

 whole. The amount, both of solids and fluids, is subject 

 to great variation, according to the amount of fluids im- 

 bibed, the action of the skin, etc. 



The average specific gravity of healthy urine is 1.020. 

 It may be measured with the urinometer, a loaded glass 

 bulb, with a graduated stem. According to a table cal- 

 culated by Dr. G. Bird, after Dr. Christisori's formula, 

 each degree of the urinometer represents 2.33 grains of 

 solids in 1000. Thus the specific gravity 1.020 represents 

 46.60 grains of solid matter in 1000 of urine. By weigh- 

 ing all the urine passed in twenty-four hours, it is easy, 

 therefore, to calculate the amount of solids secreted. 



