146 SANGUIFICATION. LECT. VII. 



Use of the Bile. I must also notice Liebig's hypotheti- 

 cal views respecting the liver. Physiologists no longer 

 regard the bile as an excretion only. This becomes obvi- 

 ous, when we remember that Berzelius found only 9 parts 

 of a matter resembling bile in 1000 parts of human excre- 

 ments ; that is to say, a man who secretes in one day from 

 500 to 700 grammes if bile, will reject with his excrements 

 only sir or ^ part only. Moreover, it cannot be supposed, 

 that a matter so slightly azotised as bile is, can be useful 

 in nutrition. Lastly, we have seen that bile performs little 

 or no part in digestion * Liebig assumes, that the bile 

 poured into the duodenum forms a soluble combination 

 with potash which is absorbed and converted into carbonate 

 of potash by yielding up a portion of its carbon to the 

 oxygen. In confirmation of these views, experiments are 

 still wanting ; and the more so, as it is only in some pa- 

 thological cases, and under certain atmospherical condi- 

 tions, that traces of biliary matter have been discovered in 

 the blood. 



Whether these hypothetical notions respecting nutrition, 

 be or be not well founded, one thing is certain, namely, 

 that an adult man absorbs in one day about 1015 grammes of 

 oxygen. The observations of Dumas, Andrat, Gavarret, 

 and the still more recent ones of Scharling, show that, on 

 an everage, a man exhales in a day 224 grammes of car- 

 bon, in the form of carbonic acid ; that men exhale more 

 than women, and children more than men ; and that more 

 is exhaled in the waking state than in sleep. A horse 

 gives out, in the form of carbonic acid, 2465 grammes of 

 carbon, consuming, for this, 6504 grammes of oxygen. A 

 milch cow exhales 2212 grammes of carbon, in the form 

 of carbonic acid, for which 5833 grammes of oxygen have 

 been consumed. The quantities of food, then, are neces- 

 sarily proportionate to the quantity of oxygen respired, and 



