Page:Popular Science Monthly Volume 67.djvu/565

fluence of Posidouius, certainly one of the most intelligent travelers of antiquity, upon writers in all departments of science is particularly marked. Strabo has preserved for us his observations in connection with Etna eruptions, with the elevation of volcanic islands, with earthquakes which happened in Phœnicia, and with a great variety of phenomena, sometimes in considerable detail, and in terms which agree closely with those of modern experience. The following graphic description of the formation of a new volcanic orifice amongst the Lipari Islands may suffice for an example:

Posidonius says, that at a time so recent as to be almost within his recollection, about the summer solstice and at break of day, between Hiera and Euonymus, the sea was observed to rise suddenly to an extraordinary height, and to abide some time raised in a compact mass and then to subside. Some ventured to approach that part in their ships; they observed the fish dead and carried by the current, but being distressed by the heat and foul smell, were compelled to turn back. One of the boats which had approached nearest lost some of her crew, and was scarcely able to reach Lipari with the rest, the men being stricken like epileptic persons, at one time fainting and giddy, and at another returning to their senses. Several days afterwards a mud or clay was observed rising in the sea, and at many points the flames issued, with exhalations and smoke; after a time the scum congealed and assumed the appearance of millstone.^[1]

Accounts of the upheaval and disappearance of volcanic islands in the Mediterranean are by no means rare in classic literature, probably the best known example being that already alluded to in connection with Thera in the year 197 B.C. On this occasion, a number of reports tell us, flames rose from the water for four days between Thera and the neighboring Therasia, so that the whole sea boiled and blazed; and little by little an island was ejected, being lifted as it were by mechanical force, and composed of volcanic rock extending over an area of twelve stadia in circumference. It is now generally admitted that the Santorin group is the basal wreck of a very large and ancient volcanic mountain, the eruptive history of which is comparatively well known. Prior to the sharp outbreak which occurred in 1866, memorable in geological annals, it was supposed that the eruption of 197 B.C. was the earliest which can be associated with the period of its human occupancy. Shortly after the last outbreak, however, relics of an ancient civilization were discovered in the islands of Thera and Therasia, buried beneath a layer of pumice-stone and other volcanic debris. As to the period of culture indicated by these remains, archeologists are agreed in referring them to the Proto-Mycenæan, which is supposed to antedate our present era by at least 2,000 years.

Eloquent testimony exists in classic literature that men were profoundly impressed even in earliest times by the class of phenomena typified by Thera and the mythical Atlantis. From the rise and dis-

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1. Strabo, VI., 2, 11. Compare also the similar accounts given by Pliny ('Nat. Hist.,' II., 19) and Aristotle ('Meteor.,' II., S, 19).