the other, and a rush of crystal rapids
sing and dance between. Of course such streams are but little affected
by the weather. Sheltered from evaporation their flow is nearly as full
in the autumn as in the time of general spring floods. While those of
the high Sierra diminish to less than the hundredth part of their
springtime prime, shallowing in autumn to a series of silent pools among
the rocks and hollows of their channels, connected by feeble, creeping
threads of water, like the sluggish sentences of a tired writer,
connected by a drizzle of "ands" and "buts." Strange to say, the
greatest floods occur in winter, when one would suppose all the wild
waters would be muffled and chained in frost and snow. The same long,
all-day storms of the so-called Rainy Season in California, that give
rain to the lowlands, give dry frosty snow to the mountains. But at rare
intervals warm rains and warm winds invade the mountains and push back
the snow line from 2000 feet to 8000, or even higher, and then come the
big floods.

I was usually driven down out of the High Sierra about the end of
November, but the winter of 1874 and 1875 was so warm and calm that I
was tempted to seek general views of the geology and topography of the
basin of Feather River in January. And I had just completed a hasty
survey of the region, and made my way down to winter quarters, when one
of the grandest flood-storms that I ever saw broke on the mountains. I
was then in the edge of the main forest belt at a small foot-hill town
called Knoxville, on the divide between the waters of the Feather and
Yuba rivers. The cause of this notable flood was simply a sudden and
copious fall of warm wind and rain on the basins of these rivers at a
time when they contained a considerable quantity of snow. The rain was
so heavy and long-sustained that it was, of itself, sufficient to make a
good wild flood, while the snow which the warm wind and rain melted on
the upper and middle regions of the basins was sufficient to make
another flood equal to that of the rain. Now these two distinct harvests
of flood waters were gathered simultaneously and poured out on the plain
in one magnificent avalanche. The basins of the Yuba and Feather, like
many others of the Sierra, are admirably adapted to the growth of floods
of this kind. Their many tributaries radiate far and wide, comprehending
extensive areas, and the tributaries are steeply inclined, while the
trunks are comparativ