Antelope Springs is in the middle of a great level plain. When the water is high it spreads into a small lake with a belt of sedge around it; when it is low there is a wide flat of black mud, glistening white with alkali in places, and the spring a water-hole in the middle. It has no flow or outlet and is fairly good water, the only drinking-place for many miles. This flat, or prairie as it would be called farther north, was the favorite feeding-ground of the Black Stallion, but it was also the pasture of many herds of range horses and cattle. Chiefly interested was the 'L cross F' outfit. Foster, the manager and part owner, was a man of enterprise. He believed it would pay to handle a better class of cattle and horses on the range, and one of his ventures was ten half-blooded mares, tall, clean-limbed, deer-eyed creatures that made the scrub cow-ponies look like pitiful starvelings of some degenerate and quite different species. One of these was kept stabled for use, but the nine, after the weaning of their colts, managed to get away and wandered off on the range. A horse has a fine instinct for the road to the best feed, and the nine mares drifted, of course, to the prairie of Antelope Springs, twenty miles to the southward. And when, later that summer Foster went to round them up, he found the nine indeed, but with them and guarding them with an air of more than mere comradeship was a coal-black stallion, prancing around and rounding up the bunch like an expert, his jet-black coat a vivid contrast to the golden hides of his harem. The mares were gentle, and would have been easily driven homeward but for a new and unexpected thing. The Black Stallion became greatly aroused. He seemed to inspire them too with his wildness, and flying this way and that way drove the whole band at full gallop where he would. Away they went, and the little cow-ponies that carried the men were easily left behind. This was maddening, and both men at last drew their guns and sought a chance to drop that 'blasted stallion.' But no chance came that was not 9 to 1 of dropping one of the mares. A long day of manoeuvring made no change. The Pacer, for it was he, kept his family together and disappeared among the southern sand-hills. The cattlemen on their jaded ponies set out for home with the poor satisfaction of vowing vengeance for their failure on the superb cause of it. One of the most aggravating parts of it was that one or two experiences like this would surely make the mares as wild as the Mustang, and there seemed to be no way of saving them from it.