Schoolboys of the thirties, forties, and fifties were told that from the bend of the Missouri to the Stony Mountains stretched an American desert. The makers of their geography books drew the desert upon their maps, coloring its brown with the speckled aspect that connotes Sahara or Arabia, with camels, oases, and sand dunes. The legend was founded upon the fact that rainfall becomes more scanty as the slopes approach the Rockies, and upon the observation of Major Stephen H. Long, who traversed the country in 1819-1820. Long reported that it could never support an agricultural population. The standard weekly journal of the day thought of it as "covered with sand, gravel, pebbles, etc." A writer in the forties told of its "utter destitution of timber, the sterility of its sandy soil," and believed that at "this point the Creator seems to have said to the tribes of emigration that are annually rolling toward the west, 'Thus far shalt thou go, and no farther.'" Thus it came about that the frontier remained fixed for many years near the bend of the Missouri. Difficulty of route, danger from Indians, and a great and erroneous belief in the existence of a sandy desert, all served to barricade the way. The flanks advanced across the states of the old Northwest, and into Louisiana and Arkansas, but the western outpost remained for half a century at the point which it had reached in the days of Stephen Long and the admission of Missouri. By 1821 many frontiers had been created and crossed in the westward march; the seaboard, the falls line, the crest of the Alleghanies, the Ohio Valley, the Mississippi and the Missouri, had been passed in turn. Until this last frontier at the bend of the Missouri had been reached nothing had ever checked the steady progress. But at this point the nature of the advance changed. The obstacles of the American desert and the Rockies refused to yield to the "heel-and-toe" methods which had been successful in the past. The slavery quarrel, the Mexican War, even the Civil War, came and passed with the area beyond this frontier scarcely changed. It had been crossed and recrossed; new centres of life had grown up beyond it on the Pacific coast; Texas had acquired an identity and a population; but the so-called desert with its doubtful soils, its lack of easy highways and its Indian inhabitants, threatened to become a constant quantity.