214 
THOMAS WALLEY. 
Fortunately, the salivary glands and the pancreas are rarely, 
practically I may say never, found diseased in the sheep. The 
stomach, being of very complex arrangement, is frequently 
deranged ; and here I should observe that the three first compart¬ 
ments of the stomach of the sheep serve a useful purpose in 
assisting to break up (comminute) and to soften the food presented 
to them and thus prepare it for the more important process to 
which it is subjected in the true digestive stomach—the fourth. 
It would be well for animals, as also for ourselves, if we could 
say the same of the liver as of the salivary glands and the pan¬ 
creas; unfortunately, there is no gland in the body more subject 
to functional and organic derangement than this. I say unfortu¬ 
nately, not only on account of its secreting bile, but on account also 
of certain processes which go on in its interior and upon which 
the support of life depends. 
In the liver, many of the constituents of the food—<s. < 7 ., the 
carbohydrates (not the fat) and, according to some authorities, 
the peptones, are converted into a substance known as glycogen , a 
sweet substance somewhat resembling sugar. Glycogen is sup¬ 
posed to be produced by the action of a ferment and to be stored 
up in the liver until required in the system, when it is reconverted 
into sugar and discharged into the circulation for the purposes of 
generating heat and muscular energy. Hence, the liver has been 
described as a “ coal bunker ” to the body. 
In addition to this function, the liver destroys the used-up red 
cells of the blood and it is from their coloring matter that the col¬ 
oring matter (pigment) of the bile, and also of the urine, is mainly 
obtained. Another important function served by the liver is to 
prevent the entrance of injurious substances into the circidation — 
to act, in other words, as a guard to the blood. Thus, the very 
substances upon which life is largely dependent, viz., the peptones, 
if taken from the intestines and injected directly into the blood 
would kill, but by passing through the liver they are not only 
rendered harmless but useful. In the intestines, peculiar poison¬ 
ous substances (ptomaines) similar to those produced in the de¬ 
composition of animal flesh, and from which so many anatomists 
and others have lost their lives by inoculation in dissecting, are 
