and Laboratory Methods. 



1849 



chlorides are decidedly increased or diminished. They are diminished in most 

 acute febrile diseases, diarrhoea, albuminuria, and in chronic diseases generally. 

 They are increased later in most of the above diseases where at first they were 

 diminished. A continued increase occurs in diabetis insipidis. 



Phosphates. — Phosphates occur in the urine in solution and in the sediment. 



In acid urine all the phosphates will be in solution. 



In alkaline urine the phosphates of sodium and potassium will be in solution. 

 The calcium and magnesium phosphates will be in the sediment. 



In ammoniacal urine the same condition occurs as in alkaline urine with 

 triple phosphate added to the sediment. 



Test for phosphates as follows : 



Fill a graduated centrifuge tube to the 10 c. c. mark with urine, add 5 c. c. 



Hand centrifuge. 



Graduated centrifuge tube. 



Electric centrifuge. 



of the magnesium mixture (ammonium chloride and magnesium sulphate, each 

 10 grams, distilled water 80 c. c, liquor ammonia 10 c. c). Thoroughly mix and 

 centrifuge for three minutes at a speed of 1000 revolutions per minute. The 

 normal quantity is from 8 to 10 per cent, as read from the percentage tube. The 

 phosphates are generally deficient in disease, occasionally they are increased. 

 They are especially deficient in chronic Bright's disease, Addison's disease, 

 pyuria, tuberculosis, carcinoma, etc. They are increased in epileptic attacks, 

 small pox, cholera infantum, etc. 



Sulphates. — The sulphates are usually in solution in the urine with the excep- 

 tion of calcium and magnesium sulphate, which when present may be found in 

 the sediment. Proceed to test for sulphates as follows : 



Fill a graduated centrifuge tube to the 10 c. c. mark with urine. Add 5 c. c. 

 of barium solution (barium chloride 10 grams, hydrochloric acid 1 c. c, distilled 



