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accuracy from the specific gravity by Christison's formula 

 (Haser-Trapp's coefficient) : "Multiply the last two figures of 

 a specific gravity expressed in four figures by 2.33. This gives 

 the quantity of solid matter in every 1000 parts." (The num- 

 ber of grams in 1000 cc). 



Example. Suppose a patient passes 1400 cc. of urine in 

 24 hours and the specific gravity is 1020, 20X2.33 = 46.6 grams 

 of solids in 1000 cc. To ascertain the amount in 1400 cc. use 

 the following proportion : 1000 cc. : 1400 cc. : : 46.6 grams is 

 to X (65.24 grams). The total quantity of the solids of the 

 human urine is about 60 grams for the 24 hours or approxi- 

 mately 4%. 



The following method taken from the Alkaloidal Clinic may 

 also be used : Multiply the quantity, in ounces, of the 24-hour 

 urine by the last two figures of the specific gravity and this 

 by 1.1, the product will represent the total solids in grains. 

 Thus, if the amount of urine voided in 24 hours be 36 ounces 

 and its specific gravity 1021, the formula would be 36X21X1-1, 

 equal to 831 grains, the normal amount for a person weighing 

 100 lbs. The amount for other weights may be determined by 

 proportion. 



In general the amount of total solids is a measure (a) of 

 the activity of tissue change; (b) of renal integrity; (c) of 

 abnormal constituents in the urine. Hygienic conditions which 

 favor increased metabolism, as abundant food, active exercise, 

 etc., increase the solid matter in urine, while the opposite con- 

 ditions decrease them. 



With the urine normal or subnormal in amount, the solids 

 are deficient pathologically from defective and enfeeMed meta- 

 bolism as in senility ; anemia as a result of syphilis, cancer, etc. ; 

 chronic alcoholism; functional or organic diseases of the liver. 

 From renal failure as in acute nephritis ; certain conditions 

 of chronic renal disease ; at the close of Bright 's disease ; 

 venous congestion of the kidneys, etc. With the urine in- 

 creased in amount there may be a deficiency of solids in dia- 

 betes insipidus; interstitial nephritis; amyloid disease of the 

 kidney; chronic parenchymatous nephritis. When the urine 

 is not increased in amount, the urinary solids are increased in 

 fevers; lithemia; some forms of dyspepsia. When the quan- 



