to a man, is filled up with divers kinds of creatures, rising one over another, by such a gentle and easy ascent, that the little transitions and deviations from one species to another are almost insensible;’ and he quotes with approbation a passage from Locke, in which we read, ‘There are some brutes that seem to have as much knowledge and reason as some that are called men[37].’ Pope, who pursues much the same track in his ‘Essay on Man,’ permits himself to speak of ‘the half-reasoning elephant.’ Any one who doubts the appropriateness of such an epithet, not only to the elephant but to many other animals, should begin to study the ways and doings of the lower creatures with an eye to this very question,--at every turn asking himself how the action observed can be accounted for by a blind irrational instinct. A stumbling horse, for example, that is generally beaten for stumbling, starts after a false step before the lash is applied. How ridiculous will it be to ascribe to horses an instinct of starting after stumbling--a conditional instinct, that appears only in those horses that have been previously beaten when they stumbled! We need not suppose, as Lord Bacon appears to have done, that ‘dogs know the dog-killer’ by a kind of power of divination[38]. By their watchful habits, and quick inference from acute observation of the few particulars they are able to comprehend, it can scarcely be doubted that dogs learn something of the dispositions and intentions of mankind, recognize their humours, and distinguish those who are friendly to themselves from those who are hostile.