In traveling with loose horses across the plains, some persons are in the habit of attaching them in pairs by their halters to a long, stout rope stretched between two wagons drawn by mules, each wagon being about half loaded. The principal object of the rear wagon being to hold back and keep the rope stretched, not more than two stout mules are required, as the horses aid a good deal with their heads in pulling this wagon. From thirty to forty horses may be driven very well in this manner, and, if they are wild, it is perhaps the safest method, except that of leading them with halters held by men riding beside them. The rope to which the horses are attached should be about an inch and a quarter in diameter, with loops or rings inserted at intervals sufficient to admit the horses without allowing them to kick each other, and the halter straps tied to these loops. The horses, on first starting, should have men by their sides, to accustom them to this manner of being led. The wagons should be so driven as to keep the rope continually stretched. Good drivers must be assigned to these wagons, who will constantly watch the movements of the horses attached, as well as their own teams. I have had 150 loose horses driven by ten mounted herdsmen. This requires great care for some considerable time, until the horses become gentle and accustomed to their herders. It is important to ascertain, as soon as possible after starting, which horses are wild, and may be likely to stampede and lead off the herd; such should be led, and never suffered to run loose, either on the march or in camp. Animals of this character will soon indicate their propensities, and can be secured during the first days of the march. It is desirable that all animals that will not stampede when not working should run loose on a march, as they pick up a good deal of grass along the road when traveling, and the success of an expedition, when animals get no other forage but grass, depends in a great degree upon the time given them for grazing. They will thrive much better when allowed a free range than when picketed, as they then are at liberty to select such grass as suits them. It may therefore be set down as an infallible rule never to be departed from, that all animals, excepting such as will be likely to stampede, should be turned loose for grazing immediately after arriving at the camping-place; but it is equally important that they should be carefully herded as near the camp as good grass will admit; and those that it is necessary to picket should be placed upon the best grass, and their places changed often. The ropes to which they are attached should be about forty feet long; the picket-pins, of iron, fifteen inches long, with ring and swivel at top, so that the rope shall not twist as the animal feeds around it; and the pins must be firmly driven into tenacious earth.