32    UNITED STATES GAZETTEER.

climate assumes a very different phase. The sea winds of the spring, summer, and early
autumn, having deposited their freight of moisture upon the summits of the intercepting
highlands, (the “Cordilleras of California") pass gently into the great valley of the Sacra-
mento, carrying a grateful softness, with scarcely a remaining vapor to obscure the brightness
of the skies. Proceeding still onward in an easterly direction, these prevailing winds climb
the flanks of the lofty Sierra Nevada, and, on reaching its elevated peaks, are deprived by
condensation of all watery particles that may yet linger among them. Thence they pass
down into the broad basin, spreading eastward to an immense extent, with occasional moun-
tainous interruptions. Here another change of climate is perceptible ; the air is exceedingly
dry and hot throughout more than half the year, and the earth suffers accordingly. These
variations occur sometimes within the distance of a few miles, corresponding generally with
the abrupt changes observable upon the face of the country. A most delightful climate per-
vades the numerous valleys on the land side of the mountains, where they are protected from
the rude ocean blasts. Near the western border of the Sacramento valley, the extremes of
temperature, between winter and summer, are very great, comprehending some 80° Fahren-
heit, viz., from 30° to 110°. A degree of heat almost as excessive as the last indicated is
often felt in various parts of the mountain region; but this is here so peculiarly modified as
to produce none of those injurious effects upon animal life which result from similar tempera-
tures elsewhere. The rainy season, sometimes termed the winter, commences at the north
in October or November, and progresses slowly to the south, reaching the centre of the state
in December, and the southern boundary in January. The season has an average duration
of about three months, but is longer and more pluvious at the north than at the south. The
effect of all these atmospheric mutations upon human health must naturally be diverse, and
not always congenial. The subject, however, has not yet been sufficiently investigated and
analyzed to enable one to treat with accuracy upon the relations between those phenomena
and the diseases incident to the localities where they respectively exist. That great scourge
of modern times, the cholera, has visited some of the most populous settlements in the state;
and other epidemics occur at different seasons, similar in character to those which visit other
parts of the world exposed to like vicissitudes and agencies.

Rivers. — The waters of California partake of those varied peculiarities which mark its
terrene surface and its atmospheric properties. The sea and its numerous contiguous bays
and estuaries, the inland lakes, the rivers and their countless tributaries, are all subjects of
speculative interest. They yield abundantly almost every description of fish found in like
latitudes, besides many kinds which are either unknown or not common in other regions.
Some of the rivers are navigable many miles from their mouths ; others flow over precipices
and ledges, constituting falls or rapids, which the industry of man may hereafter convert into
valuable mill sites. The sea-shores are prolific in marine plants, which, at some future day,
will doubtless be applied to useful purposes. Immense quantities of kelp are thrown up by
the waves — an article that now forms the most available material for the manufacture of iodine,
and is also excellent as a compost for arid soils, like those of this state. Lichens, in all their
variety, spring profusely from the rocky strand along its entire extent, which, like the mosses
of Iceland, and the carrageen of Ireland, will undoubtedly, in due time, be much prized for
their nutritive and medical properties. The coasts and inland watercourses swarm with wild
fowl, some of which resemble the aquatic birds found on the eastern shores of the continent,
and others seem peculiar to the tracts which they inhabit. The principal rivers, communi-
cating with the Pacific, are the Sacramento and San Joaquin. These flow through almost
the whole length of the great valley between the Sierra Nevada and the coast range of moun-
tains, the former taking its rise in the north, and the latter in the south, and both, uniting near
the centre of the state, pass into the noble Bay of San Francisco, whence they reach the sea.
They are fed in their course by great numbers of mountain streams from the western slopes
of the Sierra Nevada. Other important rivers, though of less considerable extent, intersect
the state in various directions.

Internal Improvements. — But little attention has hitherto been given to this subject, beyond