320 
G. ARCHIE STOCKWELL. 
It is generally believed that the fat acids saponify with the 
alkalies of the duodenum. In such case, when the alkalies are 
sufficiently abundant to decompose fat, but not sufficient to the 
formation of soap, the result must needs be an excess of fatty 
acid, and when this occurs the alkaline intestinal fluids, espe¬ 
cially the biliary secretion so essential to duodenal digestion, 
are neutraized; thus not only is the effect of the bile present 
destroyed, but in consequence thereof less bile is secreted. 
The biliary products are most essential to the absorption of 
chyle, but are not produced in sufficient quantities when the 
food is but incompletely transformed. Again, since the fasces 
almost always exhibit slight acid reaction, it is to be supposed 
that this is in consequence of the completion of the digestive 
act, and therefore not abnormal; but this acidity is increased 
or decreased from normal with the greatest facility in young 
creatures. 
All fat is not absorbed in the act of digestion, since a por¬ 
tion leaves the intestines in the form of soap, another portion 
as free fat acid, and still another comparatively unchanged. 
In diarrhoea there is a large amount of fseces, the detritus of 
which is principally casein and fat, with more or less intestinal 
epethelium. In health, on the contrary, casein is never present, 
hence its detection is prima facie evidence of over- ( 7 . e. too 
rich) feeding, or of interference with the digestive act by 
reason of an excess of free acid in the stomach. An important 
application of this fact is found in the succeeding paragraphs. 
“As it is true that fat is not completely absorbed even 
under the most normal circumstances; as free fat acids are 
easily formed and accumulated ; as they are formed in mode¬ 
rate quantities even in healthy nurslings ; as it is known that 
a surplus is very apt to derange digestion and assimilation, 
and that it even prevents the normal secretion of either of the 
digestive fluids, gastric or duodenal; as there is usually a 
superabundance of fat in the normal food of sucklings, the 
conclusion is that the greatest care should be taken to ensure 
proper food supply through the parent.” (Jacobi.) 
It is a simple matter to secure an excess of fat, but quite a 
different one, on the contrary, to secure too little, or to keep 
