FORMATION OF THE BILE. 155 



The composition of all fats lies between the em- 

 pirical formiiloo CuHjoO and C^Ji^fi. If we adopt 

 the latter, then the elements of 2 at. proteine, with 

 the addition of 2 at. oxygen and 12 at. water, will 

 yield 6 at. urea, fat (C^gHgoOg), and 12 at. carbonic 

 acid. 



It is worthy of observation, in reference to the 

 production of fat, that the absence of common salt 

 (a compound of sodium which furnishes soda to the 

 animal organism) is favourable to the formation of 

 fat ; that the fattening of an animal is rendered 

 impossible, when we add to its food an excess of 

 salt, although short of the quantity required to pro- 

 duce a purgative effect. 



54. As a kind of general view of the metamor- 

 phoses of the nitrogenised animal secretions, atten- 

 tion may here be very properly directed to the 

 fact, that the nitrogenised products of the transfor- 

 mation of the bile are identical in ultimate compo- 

 sition with the constituents of the urine, if to the 

 latter be added a certain proportion of the elements 

 of water : 



1 at. uric acid C10N4H4 Og 



1 at. urea ... C2 N2H4 O2 



22 at. water ... H22O22 



H 



f 



CioNgHgoOao 



1 at. allantoine C4N2H3 O3 "1 



7 at. water ... H7 O7 J )'■ 



C4N2H10O10 C4N2H10O10 



55. In reference to the metamorphoses of uric 



