THE TRUCKEE AND HUMBOLDT VALLEYS. 35 
sides, most of which contain clear water. A strange fact in re- 
gard to these streams, is that they run freely, even boister- 
ously, during the night and early morning, and dry up utterly 
in the lower part of their course toward noon. The power 
of the sun is such as to totally evaporate the water before 
it reaches the plains, while the powerful radiation during the 
night allows the stream to resume its proper dimensions. 
If a handkerchief be saturated with water at noonday and 
then flirted in the air, it becomes dry in a moment, thus in- 
dicating the wonderful absorptive power of the atmosphere. 
Rains are so infrequent in summer that it becomes a cause 
of wonders, not that the rills should fail, but that they 
should ever flow. Along these little streams willows, 
aspens ( Populus tremuloides), Cornus, Shepherdia and elders 
(Sambucus) grow most abundantly, and Clematis with its 
feathery plumes waves over all. The herbage is peculiarly 
interesting also, columbines (Aquilegia formosa), asters and 
solidagos, leading us away in spirit to where their beauteous 
kindred smile upon the New England autumn, while the 
gilia (G. pulchella) and lupines are equally lovely though 
less familiar. Away from the streams the wild sage only 
thrives, if so wretched a specimen of vegetable life can be 
said to flourish. By far the greater mass of the mountains is 
desert, like the plains they overlook. The great, brown 
earth waves roll down into the valleys unrelieved by a dash 
of green, except where some sombre juniper fights its hard 
battle for life. Variously colored lichens occur on all the 
rocks, and an occasional tuft of moss on those exposed to 
the streams, but ferns are nowhere seen. High up on the 
range is found a luxuriant growth of a species of Ceanothus, 
and at seven thousand feet or thereabouts, the sage yields to 
the western juniper (Juniperus occidentalis) and mountain 
mahogany ( Cercocarpus ledifolius). The latter is a hand- 
some tree, averaging twenty feet in height, with bright 
glossy leaves, whose revolute margins conceal the brown 
scurf of their inferior surfaces. Its silvery bark, the 
