In San Francisco, as well as elsewhere, there are wise men--prophets who utter their annual predictions. They say that earthquakes may be expected these days. The serve earthquake , which occurred here on the 21st of October, 1868, was so peculiar in its character, as to attract the attention of scientific men, who, in attempting to investigate the true cause, have advanced some ingenious theories.
The prevailing modern idea seems to be that earthquakes result from electrical action in the earth's crust, or in the atmosphere, simultaneous, perhaps, in both. We know that electricity is an invisible force, active or quiescent, and abounds everywhere, in a positive or negative state. When the equilibrium has been disturbed, whatever the cause, it is certain that it will be restored by a like cause. The action of the electrical forces may or may not be instantaneous. The earth is said to be a great electrical reservoir, and so, in all probability, is the atmosphere; the one positive, the other negative, generally, or at points; yet always accumulating force, quietly, or violently, in the vain endeavor to restore a perfect equilibrium. Hence, we have thunder and lightning overhead and earthquakes under foot. The forces are the same. The one is a skyquake, the other an earthquake. The one would seem to be a substitute for the other, as in California, where they never have thunder and lightning, but are amply compensated by frequent earthquakes. For eight or nine months in the year they are favored with a bright sun and a cloudless sky. When the rainy season commences, it brings with it violent electrical changes, resulting not in thunder and lightning, but in earthquakes. In this way, it may be presumed, the equilibrium is restored.
Fearful as earthquakes may seem, I doubt not, many more persons are killed by lightning than by earthquakes. The subtle influences of electricity are, indeed, mysterious, and doubtless constitute the life-principle which pervades all life, whether it be animal or vegetable.
The California Reader
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