URINE. 



217 



In chemical composition 1000 parts of urine consist of 933 to 972 

 parts of water, holding 67 to 28 parts of solid matters in solution. 

 The following analyses by Lehmann and Becquerel, present the 

 proportions of each element : 



Water 



(Solid constituents 62 

 Urea . '\ ' . 

 Uric acid . M^! '. 

 Lactic acid * . :M <j . 

 Extractive matters . 

 Lactates . ; . l J /, 

 Chlorides of sodium 



and ammonium 

 Alkaline sulphates . 

 Phosphate of soda . 

 Phosphates of lime 



and magnesia 

 Mucus 



It will be noticed that Lehmann found nearly twice the amount 

 of solids obtained by Becquerel, and about 2J times as much urea 

 and uric acid. Berzelius and Marchand agree in all these respects 

 very nearly with the former, and Simon and Dr. Miller with the 

 latter. Of course the composition of the urine varies with its spe- 

 cific gravity, and to this fact the disparity is doubtless due. Dr. 

 Christison constructed a table showing the amount of solid con- 

 stituents in urine of different specific gravities, which proves that 

 the former increase very rapidly with slight increments of the 

 latter. E. g. with a specific gravity of 1012, the solids are 27.96 

 in 1,000 ; while, if the former be increased to 1030, the latter are 

 69.90. If we look at the urea alone, we also find a rapid aug- 

 mentation as the specific gravity increases. If the specific gravity 

 is 1013.5, only 15 parts in 1,000 are urea; while, if the former be 

 1027, there will be 37.5 of urea or just 2J times as much. (Leh- 

 mann^ To reconcile the analyses of Lehmann and Becquerel, we 

 have therefore only to suppose that, while the specific weight in the 

 latter was actually 1017.01, in the former it must have been at least 

 1025. But the results obtained by Becquerel are the more valuable 



