740 
PROFKSSOIt SPOONERS ORATION. 
For it will be observed that, in addition to it, the gizzard has 
placed upon it, externally, an immensely powerful muscular con- 
tractile tissue ; it has, in fact, two muscles, which are so peculiarly 
arranged, the one with the other, as to give them the power of 
producing the act of grinding, or — if you will pardon the expres- 
sion — a millstone-like movement on the contents of the organ ; 
and thus, by the action of these muscles, the two sides of the inner 
surface of the gizzard are brought into close contact, and thereby 
a distinct grinding process is effected. This structure alone, how- 
ever, would not be competent to the desired end were it not that 
nature has ordained that, by the exercise of an instinctive faculty, 
this creature should, with the grain on which it feeds, take in 
portions of stone, which may be seen by you in the gizzard I now 
exhibit. These stones are, in fact, the agents by means of which 
the food is ground down, and, having accomplished their purpose, 
they pass through the alimentary canal unchanged. It might 
appear, at first sight, that these stones which we meet with in the 
gizzard of the fowl, and which are found in its fseces, have been 
accidentally picked up by the animal, — that it is a mere matter of 
chance, — -that the bird is incapable of distinguishing between a 
stone and a grain of wheat ; but it is not so. Nature has or- 
dained that, in the exercise of the instinctive functions of ani- 
mals, they shall never err. There is that distinction to be drawn 
between instinct and reason : reason is liable to err, but instinct 
never does. We prove this by experience. We know that if we 
deprive an animal of the means of supplying itself with stones, the 
process of digestion becomes impaired, and its life is endangered. 
These peculiarities of structure thus presented to our view must, 
I think, be calculated to impress upon our minds the importance 
of this division of our subject. I will, however, refer you to the sto- 
mach of the pig, a different kind of animal, and one of which I have 
here placed before me. Here we have a marked difference of ar- 
rangement from that developed in the horse or the ruminant. By 
far the greater part of the inner surface of the stomach is clothed 
with a villous mucous membrane ; but we perceive, at the opening 
of the oesophagus into it, there is an extension of the insensible cu- 
ticular tissue for some distance into the organ, but by no means 
to the same extent as in the horse. This is a true omnivorous 
stomach, which I recollect being pointed out by one of my old pre- 
ceptors — one whom 1 have the pleasure to see before me — Mr. 
Youatt. 
Going from the stomach of the pig to that of a dog, or a true 
carnivorous animal, we find a structure more analogous to the 
same organ in man ; and as we meet with this analogy in struc- 
ture, so also, as far as my experience goes, do we meet with rcla- 
