ABSTRACT
The summers are surprisingly hot for the latitude and elevation. Shade temperatures of more than roo0 F. are recorded a t altitudes of over five thousand feet. The average temperature for July at that height may be over 70" F., while the floors of the lower depressions may reach amazing temperatures. The highest. recorded maximum for North America comes from Death Valley in the south-west of this area where the mean July temperature is actually 102" F. The winters, on the other hand, are bitterly cold. Ten or more degrees of frost may continue for several weeks, and records of 60" below freezing point have been obtained in the more northerly parts. The light thunder-showers of summer are not extensively supplemented by winter snow, and away from the mountain ridges the total rainfall nowhere exceeds ten inches. Most of the streams depend on the high mountain snows, and many only reach the basin floors in spring, to be lost there in the sands and gravels or to flow into shallow salt lakes.
