INTESTINAL DIGESTION. 437 



and Oxygen 30.71, Ash 13.37. The mineral ash of fecal matter has been 

 examined by Enderlin j 1 who has given the following as the proportion of its 

 ingredients. 



Chloride of sodium and alkaline sulphates . . 1>367 \Soluble in water. 



Bibasic phosphate of soda 2.633 / 



Phosphates of lime and magnesia .... 80.3721 



Phosphate of iron 2.090 I Ingoluble in water 



Sulphate of lime 4.530 [ 



Silica 7.940 J 



From the later inquiries of Lehmann and others, however, it appears that the 

 proportion of salts often considerably exceeds that given by Dr. Percy, ordinarily 

 rising to 23 per cent., and even to 30 or 31 per cent., when an abundant meat 

 diet has been consumed. The potash generally predominates greatly over the 

 soda, but especially when the diet has chiefly consisted of muscular flesh. Of the 

 degree in which the bile, as a whole, enters into the composition of the feces, it 

 is difficult to speak with precision. Its coloring and its fatty matter are un- 

 doubtedly present ; but scarcely any traces of choleic acid, or of either of its 

 conjugated compounds, or of their soda-base, can be detected ; so that the proper 

 biliary matter must either have undergone decomposition, so as to be no longer 

 recognizable, or else it must have been reabsorbed. The latter is the idea now 

 usually entertained, although Valentin has endeavored to show that the proper 

 fecal matter is chiefly derived from decomposed constituents of the bile; a more 

 probable source for this, however, will be presently offered. The indications of 

 the presence of bile are more distinct, when the feces have remained for only a 

 short time in the large intestine, and when there has consequently been less time 

 for its reabsorption. In the fecal discharges which result from the action of 

 mercurials, large quantities of biliary matter may be detected, very little 

 changed. 



458. Although it cannot be stated with certainty what is the precise portion 

 of the Glandular apparatus connected with the intestinal canal, which is concerned 

 in the elimination of that peculiarly putrescent matter which gives to the feces 

 their characteristic odor, yet it may be stated almost with certainty that this 

 matter is not derived from the decomposition of the undigested residue of the 

 food. For, in the first place, this residue consists of matters whose very inapti- 

 tude for undergoing chemical change is the source of their indigestibility ; and 

 it is scarcely possible, therefore, to imagine that in so short a period they should 

 acquire a character so peculiarly offensive. But further, we observe that fecal 

 matter is still discharged, even in considerable quantities, long after the intestinal 

 tube has been completely emptied of its alimentary contents. We see this in 

 the course of many diseases, when food is not taken for several days, during 

 which time the bowels have been completely emptied of their previous contents 

 by repeated evacuations ; and whatever then passes, in addition to the biliary and 

 pancreatic fluids, must be derived from the intestinal walls themselves. Some- 

 times a copious flux of putrescent matter continues to take place spontaneously; 

 whilst it is often produced by the agency of purgative medicine. The "colliqua- 

 tive diarrhoea/' which frequently comes on at the close of exhausting diseases, 

 and which usually precedes death by starvation, appears to depend, not so much 

 upon a disordered state of the intestinal glandulse themselves, as upon the general 

 disintegration of the solids of the body, which calls them into extraordinary 

 activity, for the purpose of separating the decomposing matter which has accu- 

 mulated in it to a most unusual amount ( 418). These views (which have 

 long been taught by the author) derive a remarkable confirmation from the ex- 

 periments of Prof. Liebig on the production of artificial fecal matter. For he 



1 "Ann. der Chem. und Pharrn.," 1844. 



