THE URINE 



397 



In a urine of acid reaction we may find the following unorganized sediment: 



I. Amorphous sodium or potassium urates. Usually yellowish red. Heat and 

 alkali bring about solution. 



II. Uric acid. Whetstone crystals of yellowish-red color. Soluble in alkalis 



FIG. n;o6. Deposit in acid fermentation, a. Fungus; b, amorphous sodium urate; 

 c, uric acid; d, calcium oxalate. 



but not by heat. Abundant sediment of uric acid crystals may be due to too great 

 concentration or too great acidity of the urine rather than to the so-called uric 

 acid diathesis. 



-b 



FIG. 107. Deposit in ammoniacal fermentation, a, Acid ammonium urate, d; 

 ammonium magnesium phosphate; c, bacteria. 



III. Calcium oxalate. Octahedral crystals or dumb-bell shapes which are highly 

 refractile. Often due to diet (asparagus, tomatoes, spinach, rhubarb, etc.). 



IV. Cystin occurs in six-sided crystals which are soluble in ammonia. 



