A fourth expedition, undertaken by Fremont on his own account, resulted disastrously. The explorers foolishly tried to cross the Rocky Mountains in the middle of winter, but had to give up the attempt after many of the party had died from cold and starvation. It is hard for us to realize, now, that only sixty years ago the territory lying between the Rocky Mountains and the Pacific coast was practically unknown. Try to imagine the feelings of emigrants, bound for the gold-fields of California, who have pushed into the Great Basin without knowing where to look for grass or water. They are camped by a spring of alkaline water scarcely fit to drink; their weary animals nibble at the scanty grass about the spring; far ahead stretches the pathless desert which they must cross; upon their choice of a route their very lives will depend. Now it is all changed. The whole region is crossed and recrossed by wagon roads and railways. Many mining towns are scattered through the mountains which dot the seemingly boundless expanse of desert, while in every place where water can be found there are gardens, green fields of alfalfa, and herds of cattle. Before the year 1840 some knowledge had been acquired of the borders of the Great Basin. Trappers and explorers had crossed the Rocky Mountains and had gone down the Columbia River. There were Spanish settlements in New Mexico, Arizona, and along the coast of California. Fremont's first expedition had taken him to the summit of the Rocky Mountains in northwestern Wyoming. In 1843 he started upon the second expedition. He was at that time commissioned to cross the Rockies, descend the Columbia to Fort Vancouver, and return by a route farther to the south, across the unknown region between the Columbia and the Colorado rivers. Let us follow the little band of explorers led by Captain Fremont as day after day they made their way across what was then a trackless waste, and see what troubles they encountered because of the inaccuracy of the maps of that period. Leaving Fort Vancouver, upon the lower Columbia, for the return trip, the party ascended the river to The Dalles and then turned southward along the eastern side of the Cascade Range. They soon entered upon a region never before traversed by white men. At the time when autumn was giving place to winter, without reliable guides or maps, they were to cross the deserts lying between them and the Rocky Mountains. [Illustration: FIG. 47.--MAP OF A PORTION OF WESTERN NORTH AMERICA, MADE IN 1826 Showing the Buenaventura River]