In the first place, concurrently with his physical development, a point requiring the closest attention, the squadron horse must be trained to answer to certain conventional aids, so that any man in the squadron who applies these will find the horse answer implicitly to them. Now, let any one who wishes to study the aids exhaustively, and set up a line of conduct in the training of the horse for himself, turn a fresh young horse loose in a riding-school or enclosed manège, and keep him on the move, with a whip, if necessary. Let him note how the horse bears and uses his head, neck, leg, forehand, and haunches, as he bends and turns. The most correct aids are those indications by the reins, weight of body, legs, whip, and spur which a rider applies, so as to produce the natural preliminary attitudes for the flexion, pace, or movement desired. If the observant horseman follows this line, he will find that he must make a rule, first, not to apply unnatural aids, and secondly, not to apply more than one aid at a time in the early stages of instruction of either man or horse. Now take for instance the case of a horse which turns _on his shoulders_ at a sharp gallop; it will be noticed that he stops immediately after turning; but if, on the other hand, he turns _on his haunches_ at the gallop, it is with a view to going on in his new direction at the same or a faster pace. Therefore the rider will do well to collect his horse on the haunches as he turns at the gallop, if that is the pace at which he wishes to continue in the new direction. Whereas if he turns, meaning to stop, he will pull one--say the left--rein, and (in the later stage of the training) add the aid of the drawn-back left leg to circle the horse’s quarters round his forehand.[93] Such will be the outcome of his observations on the loose horse in the manège, and following this system he will fix in his own mind, with the assistance of the book, a list of natural aids. The fact is, that nature has taught the horse to act in such a way as to utilize the mechanism of his head, neck, body, limbs, and even tail to the greatest advantage in his movements. We note these and adapt them to the aids, which we can apply by means of our mechanical devices, such as the reins, and by our natural devices, such as the legs and the weight of the body.[94]