It was nearly half a century after the journey of Lewis and Clark that the Forty-Niners were crossing the Plains, whither, meanwhile, the Mormons had trekked in search of a country where they might live as they liked. Still the wealth of the Plains remained untouched. California was in the eyes of the world. The great cow-range was overleaped. But, in the early fifties, when the placer fields of California began to be less numerous and less rich, the half-savage population of the mines roared on northward, even across our northern line. Soon it was to roll back. Next it worked east and southeast and northeast over the great dry plains of Washington and Oregon, so that, as readily may be seen, the cow-range proper was not settled as most of the West was, by a directly westbound thrust of an eastern population; but, on the contrary, it was approached from several different angles--from the north, from the east, from the west and northwest, and finally from the south. The early, turbulent population of miners and adventurers was crude, lawless, and aggressive. It cared nothing whatever for the Indian tribes. War, instant and merciless, where it meant murder for the most part, was set on foot as soon as white touched red in that far western region. All these new white men who had crowded into the unknown country of the Plains, the Rockies, the Sierras, and the Cascades, had to be fed. They could not employ and remain content with the means by which the red man there had always fed himself. Hence a new industry sprang up in the United States, which of itself made certain history in that land. The business of freighting supplies to the West, whether by bull-train or by pack-train, was an industry sui generic, very highly specialized, and pursued by men of great business ability as well as by men of great hardihood and daring. Each of these freight trains which went West carried hanging on its flank more and more of the white men. As the trains returned, more and more was learned in the States of the new country which lay between the Missouri and the Rockies, which ran no man knew how far north, and no man could guess how far south. Now appears in history Fort Benton, on the Missouri, the great northern supply post--just as at an earlier date there had appeared Fort Hall, one of the old fur-trading posts beyond the Rockies, Bent's Fort on the Arkansas, and many other outposts of the new Saxon civilization in the West. Later came the pony express and the stage coach which made history and romance for a generation. Feverishly, boisterously, a strong, rugged, womanless population crowded westward and formed the wavering, now advancing, now receding line of the great frontier of American story.