the 26th the temperature of the earth at 53 feet below the surface (the depth then obtained in an artesian well) was 60°, the thermometer having fallen about a degree and a half for every 10 feet from the depth of 15 feet, at the time of reaching which latter depth it read 66°. September. This month was characterized by variable weather. The barn swallow made its last appearance on the 5th. On the 10th, at 5 o'clock p. m., we were suddenly visited with a high wind from a heavy bank of clouds in the southwest horizon, which at one time presented indications of approaching rain, but was intercepted by the arid mountains and high lands of Santa Cruz, Alameda, and San Francisco, where the accompanying lightning and thunder are reported to have been extremely violent.

For several days previous to the equinox a regular declension of atmospheric pressure was experienced, attended with a stagnant, sultry condition of the air. This was succeeded by a sprinkle of rain (the first of the season in this locality) at daylight on the 20th, when the lowest reading of the barometer, as above, was recorded. As the sun entered Libra, however, the weather presented one of the most favorable specimens of our autumnal climate, a fresh circulation of air being kept up by southerly breezes.

The most remarkable feature of the month was the brilliant ærolite which appeared on the evening of the 11th, at about 8 o'clock. As it was seen simultaneously in an area of several hundred miles, bounded by Red Bluffs, Iowa Hill, Stockton, San Francisco, and Santa Cruz, the probabilities are that at the time of its brief appearance it was in the upper regions of our atmosphere, and that, judging from the interval that elapsed between its explosion and the reaching of the report here, which resembled distant thunder, its distance then was between thirty and thirty-five miles. After comparing all the different accounts that have reached us, it would seem that its course was on the southern side of the zenith, from SE. to NW., and that its relative position to the point of aspect here was at first about forty degrees above the horizon, and twenty when it vanished. When first seen it appeared but little larger than Venus, but as it approached the earth it increased in size as suddenly as it diminished again just before bursting into brilliant corruscations of light that reflected all the prismatic colors. The moon was near the close of its second quarter at the time, and the atmosphere clear and transparent.

The Sacramento river fell to a lower point than has ever been before observed, which will be the zero of the scale of a new river gauge about to be constructed by the city. Its present mean temperature twelve feet below the surface reads 70°, while that of well water at the same depth is 60°. The temperature in the artesian well at sixty-five feet below the surface is 5910.

October.--The mean temperature of this month was 50.47 minus the average. On the 1st the flight of wild geese southwardly, which had been observed since the 8th September, prepared us to expect the rain that fell on five different days-the 7th, 15th, 17th, 19th, and 24th; and though not amounting to much in quantity, it was sufficient to indicate that the atmospherical changes which characterize the rainy season had set in. The first frost occurred on the 20th, and ice

formed on the 22d, at daylight. The effect of the rains and snows was sensibly demonstrated in the Sacramento river, both quantitatively and thermometrically. On the 17th, it rose suddenly ten inches, and fell again immediately to low water mark; its temperature declining 12° lower than that of the previous month. The temperature of well water fell to 57°. On the last day of the month the leaves of the willow began to fall.

November.-Although the readings of the barometer were not much below the average, more or less stormy weather prevailed over the greater part of the State. In the south, the setting in of the rains was attended by disasters of a somewhat novel character. A shower of sand swept over a portion of Los Angeles county, completely destroying the grass on the pasture lands. About the same period, severe gales prevailed at Humboldt Bay. The mornings of the 27th and 30th were unusually cold for the season. The rains of the month did not make much impression on the river, further than a rise of about 9 inches; its temperature was 46°, while that of well water was 59°. The temperature of the Artesian well, at 73 feet, where it was discontinued, stood at 58°.50. The fall of leaf of the fig, apple, pear, and cotton-wood tree occurred on the 1st, 5th, and 30th dates of the month respectively.

December.-The month was rendered remarkable for the unprecedented persistence of continuous cold weather and the number of cloudy days-much beyond the average of the three previous years. The barometer maintained an unusually high range in consequence of the prevalence of northerly winds. The readings of its extraordinary maxima were made on the evening of the 19th and morning of the 20th, while the wind was fresh from the N.NW., and the temperature ranged from 30° to 40°. Its diurnal mean fell only five times below 30 inches. The minimum was registered on the 29th at 9 p. m., preceding a SE. storm which was general throughout the State. On the same day it snowed at San Francisco, and about the same period the Coast range of mountains presented the unusual appearance of being covered with snow. The river was not much affected by the rains of the month; its temperature read 41°.

20 s

1967-1

3038

1000

72302