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of relation, such as intellect, sensation, locomotion and voice and the 
organic or vegetative functions, as digestion, absorption, respiration, 
circulation, secretion, nutrition and calorification. These functions are 
what we call life. Life means movement, which again is but a transfor- 
mation of forces contained in nature. These forces are concealed in a 
latent state in food, and their transformation into movement takes place 
within the body by means of the digestive functions. Feculents and 
sugars are consumed and provide animal heat, albuminoids and salts 
are fixed in our tissues and repair the wastes produced by use. Lastly 
fats, which have escaped oxidation are stored in the body and kept as 
a reserve for further and unforeseen wants of the organism. 
Among substances destined to repair the incessant loss of the 
animal economy, some are directly absorbed and carried at once into 
the circulatory torrent ; others deposited at the surface of the digestive 
organs, must undergo the influence of juices which are poured in and 
are modified so that they may be absorbed. This is the reason why 
food introduced into the mouth successively travels over the different 
parts of the digestive tract, being subjected by the way to various 
mechanical actions, but especially to the action of varied fluids. 
Let us take, if you please, the alimentary bole. Follow me, we 
shall accompany it in its pilgrimmage into the depths of the digestive 
tube and see what will take place. Let us suppose this alimentary bole 
composed of albuminoids, feculent and fatty substances. Once 
introduced into the buccal cavity, if finds itself in presence of a special 
liquid called saliva. The latter contains a ferment named ptyaline, which, 
while deprived of all action upon fats and albuminoids, possesses the 
property cf converting feculent substances into dextrin, rendering them, 
therefore, assimilable. Hence, the necessity of thorough mastication of 
all starchy and sugared food, in order that these compounds shall be 
well impregnated with saliva. Hence again the dyspeptic disorders 
arising with people deprived of suitable teeth, as well as those who eat 
as if they were pursued, allowing no time for this important function to 
properly take place. 
Arrived in the stomach, the alimentary bole meets with another 
liquid, the gastric juice, which, like saliva, contains a ferment called 
pepsin. The latter's task is to digest albuminoid substances, which it 
