In other words, it is upon the olfactory sense that these animals chiefly depend for their knowledge of the world. By it they are directed to their food, warned of their enemies, and attracted to their mates. Their universe is a universe of odour.
In order to become more intimate with the details of this part of our subject, we shall pass in review some of the olfactory habits and characteristics of the macrosmatic animal most familiar to us, namely, the dog.
There can be no doubt of the all-important part that smell plays in the life of the dog. Every one is familiar with it, and yet we do not often stop to think what its meaning is for the canine brain and understanding. One of the mysteries that must, one would suppose, for ever remain hidden from us, is what aspect the world we both share in company bears to this our closest animal friend. Who can tell what is passing through his mind as he sniffs at us ? He can recognise his master by sight, no doubt, yet, as we know, he is never perfectly satisfied until he has taken stock also of the scent, the more precisely to do so bringing his snout into actual contact with the person he is examining. It is as if his eyes might deceive him, but never his nose.
The greyhound courses by sight, but all other dogs hunt by scent, and the speed and certainty of foxhounds in full cry bear a new significance
