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of 1864, and that of the latter season in the early part of 1866, leaving the intervening calendar year deficient.
In seasons of scanty rains, the deficiency is not confined to certain districts, as in the Atlantic States, but it is general. The annual supply, however, varies greatly in different sections. Taking the guage at San Francisco as a basis, very nearly the same quantity falls in the valleys surrounding the bay, and also in the Sacramento valley as far north as the Capital. Speaking more precisely, the quantity in Sonoma and Napa counties is rather greater, and in Santa Clara, south of the bay, rather less than at San Francisco. Proceeding southward it diminishes rapidly, the rain fall at Los Angeles and San Diego being only one half that of the bay. In the north and northeast, among the Sierras, it is three or four times as much in some localities.
The following table exhibits the rains of each month at San Francisco, for seventeen years, beginning with the winter of 1850—51, and the mean for each month of the year:
The greatest quantity of rain for any one month, as the table shows, was 18.14 inches, in January, 1862—a winter memorable on account of destructive floods on the Pacific slope. The greatest quantity in any one month in Eastern Pennsylvania, during a period of thirty years, was thirteen inches; and this was in one of the summer months. So much as this never falls in a winter month in the Atlantic States. For one season of excessive drought there have been two of excessive rain. No two seasons in succession have given as much rain as 1866-67, and 1867-68.
The rains of each season are exhibited in the following table, in juxtaposition with the rains of each year:
It appears that December is the month of greatest rain. The rainy tendency reaches its climax about Christmas, and then diminishes gradually until the termination of the season of rain, towards the latter end of May. June, July, August and September are dry, with exceptions so slight as scarcely to deserve notice, only 2.50 inches having fallen in these four months collectively in seventeen years.
In almost every winter there are two rainy periods, with a drier period interposed, showing an analogy to the earlier and later rains of Palestine and other oriental countries. The month of February is the most frequent representative of the dry period. But the spring rains, which sometimes commence in this month, and other heavy rains which occasionally fall, swell the aggregate so as to prevent the exhibition of a deficiency in the table.
In speaking of the "rainy season," strangers will not infer that rain is perpetual, or nearly so, during that time. The term is employed only in contrast with the dry season, and it implies the possibility rather than the actual occurrence of rain. In more than half the winters there is not a drop beyond the necessities of agriculture, and even in the seasons of most rain much very pleasant weather is interspersed. If the winter be not extraordinary, it is generally regarded as the most pleasant season of the year. In the intervals of rain it is bright, sunny and calm. It is spring rather than winter. The grass starts as soon as the soil is wet. At Christmas, nature wears her green uniform almost throughout the entire State, and in February and March it is set with floral jewels. The blossoms increase in variety and profusion until April, when they are so abundant in many places as to show distinctly the yellow carpeting on hills five miles distant.
There is great irregularity in the time of the commencement of the rainy season. It never sets in before November, and sometimes not till the latter part of December. In the northern section the rains commence earlier than at San Francisco, and in the southern section later. The spring rains, which are of immense importance to agriculture, rarely fail. March is one of the surest months in this respect. April often gives a copious supply. There is a remarkable tendency to rain about the 20th of May, and a complete cessation soon afterwards. It is a striking feature of the climate, that when the weather puts on its rainy habit, the rain is apt to continue every day for one or two weeks, and then an interval may ensue without a drop for several weeks.
The rains of California are tropical in one respect, being showery, and not often regularly continuous for many hours. The monotony of an easterly storm, such as the Atlantic climate furnishes, is almost unknown here. The sun breaks forth frequently in the midst of a shower, and directly the sky is almost clear. Presently, when it is least expected, the rain is heard on the roof with the suddenness of a showerbath.
The night is more favorable to rain than the day. No matter how dense the clouds, how fair the wind, how resolute the barometer in its promise of falling weather, the sun rarely fails to break up the arrangement before noon, and to tumble the clouds into confused masses, or dissipate them altogether. But before night, or during the night, the clouds resume their function.
The prevailing direction of the cloud-current is from south to west, and the cloud supplying the rain is mostly of the cumulo-stratus or nimbus form, and quite low in the sky. What is singular, the rain begins most frequently to the northward, although the cloud comes from the south. The horizon in the south may be entirely clear under these circumstances, the cloud forming in view, and growing denser and denser in its northward travel, until it precipitates the rain.
The following table exhibits the mean quantity of rain falling at different stations, and the number of years on which the mean is computed. The stations are arranged in the order of their latitude, beginning with Fort Yuma and San Diego, which are about on the same parallel:
A comparison with the Atlantic slope presents a striking contrast. The smallest amount of rain that falls in one year, in any locality on the eastern side, say twenty inches, is at least equal to the average annual supply in the great grain-growing valleys of California; whilst, on the other hand, no locality on the eastern side, until you reach the tropical latitude of Florida, approaches the maximum of the Pacific slope. Thus, California, with a range of ten degrees of latitude, has a minimum of three and one-quarter inches at Fort Yuma, with a maximum exceeding one hundred inches on the Sierras; whilst the Atlantic slope, with upwards of twenty degrees of latitude, and an expanse of territory vastly greater, with mountainous elevations of considerable height, presents a minimum of twenty inches with the same maximum as California.
To make the contrast more striking, it may be added that the annual supply of rain has a greater range in California, in a distance of fifty miles from Sacramento City, than on the Atlantic slope, from Maine to Florida. Two or three times as much rain may fall in a single night in the mountains of California, as in the entire year in the southeastern corner of the State.
The enormous quantity of one hundred and twenty-nine inches, at Hoopa valley, is stated on the authority of Dr. Kirkpatrick, of the United States Army. In general, such extreme results are to be accepted with caution. The guage may not have been fairly exposed—or it may have been wrongly graduated. But Dr. Kirkpatrick gives, in detail, the supply for each of three months, which seems to confirm his report: November, 44.10 inches; December, 23.79 inches; January, 30.95 inches. An observer on the South Yuba, Nevada county, reports 41.95 inches as falling there in the month of December, 1867. Instead of being surprised at the floods in the Sacramento valley, we may wonder what becomes of so much water.
It is worthy of note, that Hoopa valley is but about forty miles west of Fort Jones, where the annual supply is set down as 16.77 inches. Both places are on the northern border of the State, among the coast mountains, and remote from the ocean.
SNOW AND HAIL--- LIGHTNING AND THUNDER—AURORA BOREALIS.
There are no snow storms worthy of the name in the bay region, or in the great valleys of the State. Hail falls frequently in some seasons, mingled with rain showers—that is to say, it falls three or four times during the winter, in which case the winter is pronounced a hard one. Three or four times in eighteen years there has been enough to cover the ground, so that in favorable spots it would remain an hour or two. Once or twice in the same period the southern and middle sections of the State have been covered with snow. On the 29th of December, 1856, it snowed very fast for several hours, and two or three inches collected on the ground at San Francisco. It melted, however, before night. On the hills surrounding the bay it remained nearly a week. Early on the morning of the 12th of January, 1868, it snowed very fast for an hour or two, so that two inches collected. But it disappeared before sunrise, and was therefore invisible to the citizens generally.
The winter seldom passes without exhibiting the summits of Monte Diablo and the Coast Range, as seen from the metropolis, covered with snow. In the most severe winters it may remain there two or three weeks at a time, but this seldom happens. When it rains at San Francisco with the temperature below 50°, it snows generally on those mountains.
But, in this region of contrasts, while snow is a phenomenon in the central valleys, it accumulates in enormous quantities in the mountainous counties of the north and east. The stories that are told of its depth in some localities are almost incredible—not on the Alpine heights, in the region of perpetual snow, for there is perpetual snow only in a few places in California—but in mining regions and mountain valleys, inhabited by a dense population, and producing a luxuriant growth of vegetation in the summer. We have been assured that forfrv feet accumulated in one locality, in the winter of 1866-7, as measured on the trunks of trees. When we reflect that one inch of rain is equiva