AGRICULTURE AND SOILS OF CALIFORNIA. A81 
clear sky, it sweeps over the mountains, accompanied by clouds of dust, 
and, like the hot breath of a furnace, it licks up all moisture before it, 
wilting and withering the leaves of all but the most hardy plants, crack- 
ing and baking the soil, loosening the joints of all wooden structures, 
whether wagons, furniture, or houses, and causing the latter to resound 
at night with the splitting of panels and similar unearthly noises, to the 
discomfort of the nervous sleepers, that at such times comprise the vast 
majority of the population. This universal infliction fortunately lasts 
but rarely more than three days, when the welcome sea-fog, which has 
been kept standing like a wall forty or fifty miles in the offing, gradu- 
ally advances, and with its grateful coolness and moisture infuses fresh 
life into the parched vegetation and the irritable, panting population. 
During the winter months the north wind is equally dry, but at the 
same time cold; and while it then sometimes lasts a week or more, it 
causes but little discomfort or damage, save occasionally to the young 
grass and grain. The second distinctive feature of the coast climate is 
the fogs brought in from the sea by the prevailing west winds or sum- 
mer trades, as the result of their crossing the cold Alaskan current in- 
shore. The sea-fogs, coming in regularly almost every afternoon from 
the latter part of June to that of August, and more or less throughout 
the year, oiten with a gorgeous display of cloud pictures, temper mate- 
rially not only the heat, but also the summer drought; so that under 
their influence plants requiring but a moderate degree of moisture can, 
in a loose soil, grow throughout that season. In the latitude of San 
Francisco it thus happens that in the coast climate sub-tropical and 
northern plants may thrive side by side; the latter (such as currants 
and cranberries) ripening with ease and in great perfection, while the 
fig, grape, orange, &c., though growing luxuriantly, can ripen their 
fruit only in valleys protected by mountain ridges from the direct influ- 
ence of the summer. trade-winds. Thus while a broad river of fog may 
be pouring in at the Golden Gate, covering the two cities and spreading 
out on the opposite shore to a width of eight or ten miles, the hamlet of 
San Rafael, only fourteen miles to the north, but under the lee of Mount 
Tamalpais, and the old town of San José, under the protection of its 
seaward mountains, forty miles to the south, are mostly basking in full 
sunshine, and ripen to great perfection not only the grape, but also the 
more tender fruits of their groves of fig and orange. 
2. Climate of the great interior valley.—The average winter temperature 
is lower than that of corresponding portions of the coast, although the 
minimum is little, if at all, below that of the latter. Sub-tropical plants, 
therefore, winter there almost as readily as on the coast. In summer, 
however, the average temperature is high, often remaining above 100° 
Fahrenheit for many days, the nights also being very warm. At the 
same time, however, the air is so dry as to render the heat much less 
oppressive than is the case east of the mountains, sunstroke being 
almost unknown. Standing on the summits of the Coast Range in sum- 
mer, and looking down upon the thick shroud of fog covering all to sea- 
ward, the white masses can be seen drifting against the mountain side, 
and, rising upward, dissolving into thin air as soon as, on passing the 
divide, they meet the warmth of the Great Valley. From points in the 
latter the cloud-banks may be.seen filling the mountain passes and some- 
times pouring like a cataract over the summit ridges, but powerless to 
disturb even for a moment the serenity of the summer sky, or to yield a 
drop of moisture to the parched soil of the San Joaquin Plains. The 
unwary traveler, starting from Sacramento or Stockton on a hot sum- 
mer’s day without the thought of shawl or overcoat, may find himself 
31 AGR 
