470 LIQUID PARTS OF ANIMALS. 



Potash, . . 2-051 



Ammonia, . . 0*130 



Urea, . . 23-640 



38-276 



and I considered that these substances were combined so as to 

 form the following bodies : 



Urate of ammonia, . 0-298 

 Sal-ammonia, . 0*459 



Sulphate of potash, . 2-112 

 Chloride of potassium, 3-674 

 Chloride of sodium, 1 5 -060 



Phosphate of soda, -i ; 4*267 

 Phosphate of lime, . ' 0-209 

 Acetate of soda, '*- 2-770 

 Urea with colouring matter, 23-640 



52-489 



The rest of the weight consisted of water together with a free 

 acid, which may be the lactic.* 



But by far the most numerous set of experiments on the con- 

 stitution of urine has been made by M. Lecanu. His object was 

 to determine the quantity of urine voided in twenty -four hours, 

 its specific gravity, and the weight of the urea, uric acid, and salts 

 which each urine contained. Before giving the table of his re- 

 sults, it will be worth while to state the general facts brought to 

 light by his numerous experiments. They may be stated very 

 shortly. 



1. The urine of young men has usually a higher specific gra- 

 vity than that of old men or infants. 



2. The quantity of urea voided in twenty-four hours is very 

 different in different individuals. One man, for instance, voided 

 509*3 grains, and another only 185*3 grains. 



3. But in the same individual the quantity of urea voided in 

 twenty-four hours does not vary much, as will appear from the 

 following table of Lecanu :f 



In A,J it varied from 334-9 grains to 478-4 grains. 

 B, . 360-4 . 478-4 



* Records of General Science, ii. 13. f Jour, de Pharmacie, xxv. 746. 

 % These letters refer to the individuals whose urine is given in a subsequent 

 table. 



