Today in Earthquake History

In the second year of the reign of Valentinian and Valens, on the morning of the twenty-first day of July, the greatest part of the Roman world was shaken by a violent and destructive earthquake. The impression was communicated to the waters; the shores of the Mediterranean were left dry by the sudden retreat of the sea; great quantities of fish were caught with the hand; large vessels were stranded on the mud; and a curious spectator amused his eye. or rather his fancy, by contemplating the various appearance of valleys and mountains which had never, since the formation of the globe, been exposed to the sun. But the tide soon returned with the weight of an immense and irresistible deluge, which was severely felt on the coasts of Sicily, of Dalmatia, of Greece, and of Egypt; large boats were transported and lodged on the roofs of houses, or at the distance of two miles from the shore; the people, with their habitations, were swept away by the waters; and the community of Alexandria annually commemorated the fatal day on which fifty thousand persons had lost their lives in the inundation.
From The Decline and Fall of the Roman Empire, by Edward Gibbon.