A description of the equipment of a mule-train and the method of packing, together with some of the curious facts connected with its movements, may not be uninteresting, particularly as the whole thing, with rare exceptions in the regular army at remote frontier posts, has been relegated to the past, along with the caravan of the prairie and the overland coach. To this generation, barring a few officers who have served against the Indians on the plains and in the mountains, a pack-mule train would be as great a curiosity as the hairy mammoth. In the following particulars I have taken as a model the genuine Mexican pack-train or atajo, as it was called in their Spanish dialect, always used in the early days of the Santa Fe trade. The Americans made many modifications, but the basis was purely Mexican in its origin. A pack-mule was termed a mula de carga, and his equipment consisted of several parts; first, the saddle, or aparejo, a nearly square pad of leather stuffed with hay, which covered the animal's back on both sides equally. The best idea of its shape will be formed by opening a book in the middle and placing it saddle-fashion on the back of a chair. Each half then forms a flap of the contrivance. Before the aparejo was adjusted to the mule, a salea, or raw sheep-skin, made soft by rubbing, was put on the animal's back, to prevent chafing, and over it the saddle-cloth, or xerga. On top of both was placed the aparejo, which was cinched by a wide grass-bandage. This band was drawn as tightly as possible, to such an extent that the poor brute grunted and groaned under the apparently painful operation, and when fastened he seemed to be cut in two. This always appeared to be the very acme of cruelty to the uninitiated, but it is the secret of successful packing; the firmer the saddle, the more comfortably the mule can travel, with less risk of being chafed and bruised. The aparejo is furnished with a huge crupper, and this appendage is really the most cruel of all, for it is almost sure to lacerate the tail. Hardly a Mexican mule in the old days of the trade could be found which did not bear the scar of this rude supplement to the immense saddle.