We were four hours reaching the highest point, climbing for over a mile over shelly, feldspathic granite, after leaving our horses at the limit of pines.

The view from this peak commanded completely the lake, enabling us to sketch a map of its inlets and bearings with considerable accuracy.

On the southwestern portion of the lake rose a high mountain of a yellow rock, forming a divide or water-shed in the center of the great basin, beyond which the waters flowed south and west.

This valley has a uniform width of about three miles, is level and swampy through its whole extent, with numerous lakelets of considerable size scattered at intervals over its surface.

South of Bridger's Lake, and beyond the Snake River divide, were seen two vast columns of vapor, thirty miles away, which rose at least 500 feet above the tops of the hills.