NUTRITION. 7 
The ORGANS OF NUTRITION occupy the greater part of the space between the 
diaphragm and the lower limbs, and are composed of the following parts. The mouth 
receives and, in most cases, grinds the food until it is sufficiently soft to be passed onwards 
into the general receptacle, called the stomach. Here begins the process of digestion, 
which is chiefly carried on by means of a liquid called the gastric juice, which is secreted 
by glands within the stomach, and dissolves the food until it is of an uniform soft 
consistency. In this state the food is called “chyme,” and passes from the stomach 
into a tube called the “duodenum.” Here the chyme begins to separate into two 
portions ; one, an indigestible and useless mass, and the other, a creamy kind of liquid, 
ralled “chyle.’ The former of these substances is propelled through the long and 
rariously-formed tube, called the intestinal canal, and rejected at its outlet; while 
the chyle is taken up by numerous vessels that accompany the intestines, and is finally 
thrown into one of the large veins close by the heart, and there mixes with the blood. 
There is another curious system called the “lymphatic,” on account of the limpid 
appearance of the liquid which is conveyed through the lymphatic vessels. These are 
analogous to the lacteals, but imstead of be longing to the intestines, they are spread over 
the whole frame, being thic kly arranged just under the skin. They are curiously 
shaped, being studded with small knotty masses, and fitted with valves which keep 
the contained liquid in its proper course. Both the lacteal and lymphatic vessels pour 
their contents into one large trunk, called from its position the thoracic duct. This 
vessel is about twenty inches in length, and when distended, is in its widest part as 
large as a common lead pencil. 
All these wonderful forms and organs would, however, be but senseless masses of 
matter, differmg from each other by the arrangement of their component parts, but 
otherwise dead and useless. It needs that the being which is enshrined in this bodily 
form (whether it be man or beast) should be able to move the frame at will, and to 
receive sensations from the outer world. 
More than this. As all vertebrated animals are forced at short intervals to yield 
their wearied bodies to repose, and to sink their exhausted minds in the temporary 
oblivion of sleep, there must of necessity be a provision for carrying on the vital 
functions without the active co-operation of the mind. Were it otherwise, the first 
slumber of every being would become its death-sleep, and all the higher classes of 
animals would be extirpated in a few days. The mind would be always on the 
stretch to keep the heart to its constant and necessary work ; to watch the play of the 
lungs in regenerating the blood; to aid the stomach in digesting the food, and the 
intestinal canal in sifting its contents ; together with many other duties of a character 
quite as important. 
Supposing such a state of things to be possible, and to be put in practice for one 
single hour, how terrible would be the result to humanity! We should at once 
decenerate into a mass of separate, selfish individuals, each thinking only of himself, 
and foreed to cive the whole of his intellectual powers to the one object of keeping 
the animal frame in motion. Society would vanish, arts cease from the face of the 
earth, and the whole occupation of man would be confined to living an isolated and 
almost vegetable life. 
This being the case with man, the results to the lower portions of the animal 
kingdom would be still more terrible. For their intellect is infinitely below that of 
the dullest of the human race, and they would not even possess the knowledge that 
any active exertion would be necessary to preserve their lives. And for all living beings 
the wandering of the mind but for a few seconds would cause instantaneous death. 
All these difficulties are removed, and the animal kingdom preserved and. vivified, 
by means of certain vital organs, known by the name of nerves. 
Tt is clear enough that mind does not act directly upon the muscles and the various 
organs of the material body, but requires a third and intermediate substance, by which 
it is enabled to convey its mandates and to receive information. The necessarily 
multitudinous channels through which this substance is conveyed are called “ nerves,” 
and are of a consistency more delicate than that of any other portions of the animal 
