Another curious emotional feature in the horse is the liability of all the other mental faculties of the animal to become abandoned to that of terror. For I think I am right in saying that the horse is the only animal which, under the influence of fear, loses the possession of every other sense in one mad and mastering desire to run. With its entire mental life thus overwhelmed by the flood of a single emotion, the horse not only loses, as other animals lose, 'presence of mind,' or a due balance among the distinctively intellectual faculties, but even the avenues of special sense become stopped, so that the wholly demented animal may run headlong and at terrific speed against a stone wall. I have known a hare come to grief in a somewhat similar fashion when hotly pursued by a dog; this, however, was clearly owing to the hare looking behind instead of before, in a manner not, under the circumstances, unwise; but, as I have said, there is no animal except the horse whose whole psychology is thus liable to be completely dominated by a single emotion.
As for its other emotions, the horse is certainly an affectionate animal, pleased at being petted, jealous of companions receiving favour, greatly enjoying play with others of its kind, and also the sport of the hunting-field. Lastly, horses exhibit pride in a marked degree, as do also mules. Such animals, when well kept, are unmistakably pleased with gay trappings, so that 'in Spain, as a punishment for disobedience, it is usual to strip the animal of its gaudy coronal and bells, and to transfer them to another' (Thompson).
The memory of the horse is remarkably good, as almost every one must have had occasion to observe who has driven one over roads which the animal may have only once traversed a long time before. As showing the duration of memory I may quote the following letter to Mr. Darwin from the Rev. Rowland H. Wedgwood, which I find among the MSS. of the former:—
I want to tell you of an instance of long memory in a horse. I have just driven my pony down from London here, and though she has not been here for eight years, she remembered her way quite well, and made a bolt for the stables where I used to keep her.
A few instances of the display of intelligence by members of the horse tribe may bring this section to a close.
Mr. W. J. Fleming writes me concerning a vicious horse he had which, while being groomed, frequently used to throw a ball of wood attached to his halter at the groom. He did so by flexing his fetlock and jamming the ball between the pastern and the leg, then throwing the ball backwards 'with great force.'
I myself had a horse which was very clever at slipping his halter after he knew that the coachman was in bed. He would then draw out the two sticks in the pipe of the oat-bin, so as to let all the oats run down from the bin above upon the stable floor. Of course he must have observed that this was the manner in which the coachman obtained the oats, and desiring to obtain them, did what he had observed to be required. Similarly, on other occasions he used to turn the water-tap to obtain a drink, and pull the window cord to open the window on hot nights.
The anecdote books contain several stories very much alike concerning horses spontaneously visiting blacksmiths' shops when they require shoeing, or feel their shoes uncomfortable. The appended account, vouched for as it is by a good authority, may be taken as corroborative of these stories. I quote the account from 'Nature' (May 19, 1881):—