Oct. 21st, 19h. 45m.—A smart shock of an earthquake was felt in San Francisco. The buildings situated over the water were violently shaken. There was much commotion in the water of the harbor a few minutes preceding the shock, which caused several vessels to heave heavily at their hawsers and cables. Oct 27th, 15h.—A light shock was felt in the valley of Clear Lake. On the same day a shock was felt at Downieville, which lasted about five seconds. At Goodyear’s Bar it was more severe than at the preceding locality. Dec. 5th, 11h. 20m.—The shock of an earthquake was felt at Humboldt Bay, which lasted about three seconds. There were two vibrations, the last being the most severe. Dec. 11th, 4h.—A shock was felt in San Francisco and at the Mission Dolores; at the latter place it is represented as being quite severe. The whole number of which I have a record for 1855, amounts to twelve only; but there may be others which have escaped my notice on account of absence from the city. The following table will show the number of shocks for each year, and each month of the year, for six years from 1850 to 1855, inclusive. ----------------+-----+-----+-----+-----+-----+-----+------- | | | | | | |No. for | | | | | | |each |1850 |1851 |1852 |1853 |1854 |1855 |month | | | | | | |in six | | | | | | |years. ----------------+-----+-----+-----+-----+-----+-----+------- January, | — | — | — | 2 | 1 | 2 | 5 February, | — | — | — | 1 | — | 1 | 2 March, | 1 | — | — | 1 | 2 | — | 4 April, | — | — | — | 2 | 1 | 1 | 4 May, | 1 | 3 | — | — | 2 | — | 6 June, | 1 | 1 | — | 1 | 1 | 1 | 5 July, | — | — | — | 1 | 2 | 1 | 3 August, | 1 | — | — | — | — | 1 | 2 September, | 1 | — | — | 1 | 1 | — | 3 October, | — | — | — | 2 | 2 | 2 | 6 November, | — | — | 11 | 2 | — | — | 13 December, | — | 2 | 1 | 2 | — | 2 | 8 ----------------+-----+-----+-----+-----+-----+-----+------- Total each year,| 5 | 6 | 12 | 14 | 12 | 11 |= 59 ----------------+-----+-----+-----+-----+-----+-----+------- From the above it will be seen that of the total number of shocks in six years in this State, forty-eight have occurred during the spring, summer, and autumn months, and eleven during the winter months.