Volcanoes and earthquakes

On the morning of May 8th, 1902, the clocks of St. Pierre ticked on towards ten minutes of 8 when they would stop forever. Against a background of bright sunshine, a huge column of vapour rose from the cone of Mont Pelée.

A salvo of reports as from heavy artillery. Then, choked by lava boiled to white heat by fires in the depths of the earth, Pelée with a terrific explosion blew its head off.
— Fairfax Downey, ‘Last Days of St. Pierre’, in Disaster Fighters, G. Putnam’s Sons.

… and the mount of Olives shall cleave in the midst thereof toward the east and toward the west, and there shall be a very great valley; and half of the mountain shall remove toward the north, and half of it toward the south.
— Holy Bible, Zechariah, 14:4.

Naturally a good deal of thought has been given to how the immense energy of volcanoes might be harnessed for man’s use. It has been done on a relatively minor scale in several countries, notably Italy and Iceland.
— A. E. Benfield, ‘The Earth’s Heat’, Scientific American Reader (1953), 86.

In the afternoon of the 22nd a slight shock of an earthquake was observed, which lasted two or three seconds, and was accompanied with a distant noise like the report of a cannon, coming from the southward; the shock was local, and so slight that many people did not feel it.
— David Collins (1756 – 1810), An Account of the English Colony in New South Wales, (published 1798, here describing events in July 1788).

Just as the level of Stone Age finds gives an average sinkage of 9 inches in a hundred years, so calculations based on Roman remains suggest a similar figure… Presumably it is still doing so to-day, although it will be another five hundred or a thousand years before the problem of maintaining the Thames embankment will begin to become acute.
— A. W. Haslett, Unsolved Problems of Science, London 1937. (The Thames Barrier went into operation in 1986!).

All things have second birth;
The earthquake is not satisfied at once.
— William Wordsworth (1770 – 1850), The Prelude.

It cannot therefore be doubted that the extensive volcanic elevations constituting the high table-land of Armenia and the island Iceland have flowed from sources which were chemically identical. The idea that perhaps all the volcanic formations on the earth’s surface have originated from the same source, or even, indeed, that it is from this very source that all the ferruginous and non-ferruginous rocks have originated by fusion together, is rendered the less improbable by the fact that the mineralogical differences between those Caucasian and Icelandic rocks which present the same mean composition, are not less marked than those observed among other ferruginous rocks of plutonic origin. It would therefore be very interesting to trace the genetic relations existing among the more ancient formations, in a manner similar to that which I have adopted with regard to the volcanic rocks. It would be necessary to select for this purpose only the more extensive and largely developed rock systems, in order to avoid those disturbing influences which may have resulted from the contact of chemically metamorphosed exogenous rocks with those of plutonic origin. These disturbing influences manifest themselves even where volcanic rocks have penetrated in isolated elevations, through calcareous or siliceous sedimentary beds.
— Robert Wilhelm Bunsen (1811 – 1899), ‘On the processes which have taken place during the formation of the Volcanic Rocks of Iceland’, Poggendorff’s Annalen, 1851, No. 6, translated in the Scientific Memoirs, edited by Tyndall & Francis, 1853.

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