Humboldt River, a stream which rises in the N. E. part of Nevada in Elko county, flows first "W. by S., then bends N., and afterward flowing S. S. "W. loses itself after a winding course of about 300 m. in the Humboldt " sink " or lake, on the border of Humboldt and Churchill counties, in the W. part of the state. It is in no part more than a few yards wide, and is not navigable. It flows through a treeless region, the valley, except immediately along the stream, consisting of sandy land covered with sage brush, which, however, by irrigation might be rendered productive. Numerous streams on either side of the valley rush down the mountain gorges, but sink before reaching the. Humboldt, except in the case of a few in seasons of more than usual snow and rain in the mountains. Of these streams the principal are the Little Humboldt on the north, and Reese river on the south. Near its source in Elko county, the Humboldt receives its N. and S. forks. As the only considerable stream flowing E. and W. through the Great Basin, its valley formed the ordinary emigrant route from the Great Salt lake to California; the Central Pacific railroad now follows its banks throughout its whole course.

The Humboldt "sink" has no outlet, and is merely a marshy spot in a sandy plain, 10 or 15 m. long and 30 or 40 m. in circumference; the extent of water surface is variable, the capacity of the sands to absorb and of the atmosphere to evaporate being generally in excess of the supply from the river.