SENSE OF SMELLING. 
73 
shift for himself—or, if worked by day, usually turned out at 
night—the olfactory nerve is nearly as large as that of the horse, 
and, comparing the bulk of the two brains, a great deal larger. 
The olfactory nerve of the sheep and the swine is comparatively 
as large as that of the ox, or more so, and for the reason already 
assigned ; and, lastly, observe in the dog the still greater bulk 
of this important portion of the brain. 
The comparative Bulk of the JEthmoid Bone .—I have said 
that we can plainly trace the nervous pulp over the aethmoid 
and upper turbinated bones; we suppose that it spreads over, 
but not in so great a quantity, the other contents of the nasal 
cavity. See then the increased bulk of the aethmoid bone of the 
horse compared with the human being: the aethmoid bone of the 
ox is considerably larger ; that of the sheep larger still ; and 
that of the dog occupying the whole of the upper part of the ca¬ 
vity, and thrusting the cornets from their situation, and render¬ 
ing them comparatively diminutive and insignificant. 
The Acuteness of Smell in different Animals. —Observe all our 
domesticated animals how carefully they examine their food and 
their water, and judge of their good or bad qualities by the 
smell. They submit every stranger to the scrutiny of this sense, 
and form their opinion of him, and even of his intentions, by the 
intelligence which they obtain through its medium. 
In the Dog. —Passing by all the others, we trace in the dog 
the triumph of olfactory power. How indistinct must be that 
scent which is communicated to, and lingers on the ground, by 
the momentary contact of the foot of the hare, the fox, or the 
deer ! Yet the hound, of various breeds, recognises it for hours, 
and, some sportsmen have said, for more than a day ; and he 
can not only distinguish the scent of one species of animal from 
another, but that of different animals of the same species. The 
fox-hound, well broken in, will rarely challenge at the scent of 
the hare, nor will he be imposed upon when the crafty animal 
that he pursues has himself taken refuge in his earth, and thrust 
out a new victim before the pack. 
The bloodhound in former days, and even in modern times, 
cruelly and disgracefully trained to the scent of the human 
being, but now in his legitimate office the guardian of the deer 
or of the mansion, gives interesting proof of almost incredible 
acuteness of smell. 
A miscreant had broken into a gentleman’s stable, and muti¬ 
lated some of his horses. When this was discovered on the fol¬ 
lowing morning, a bloodhound was brought out. After awhile 
he hit off the scent, and followed it more than fifteen miles, 
lie then bayed at a cottage door, and, the door being opened, he 
