In all these flood stories of Greece we cannot doubt that the tradition of a cataclysm fatal to the whole of humanity--a tradition common to all Aryan peoples--was mixed up, as Knobel rightly observes, more or less precisely with local catastrophes produced by extraordinary overflows of lakes or rivers, or the rupture of their natural embankments, the sinking of some portions of the sea-coast, or tidal waves consequent upon earthquakes or sudden upheavals of the ocean bed. Such events were frequent in Greece, in the district between Egypt and Palestine, near Pelusium and Mount Casius, as well as in the Cimbric Chersonese. The Greeks used to relate how often their country had in primitive ages been the theatre of such catastrophes. Istros numbered four of these, one of which had opened the Straits of the Bosphorus and Hellespont, when the waters of the Euxine, rushing into the Ægean, submerged the islands and neighbouring coasts. This is evidently the Deluge of Samothracia; where the inhabitants who succeeded in saving themselves did so only by gaining the highest peak of the mountain that rises there; then, in gratitude for their preservation, consecrated the whole island by surrounding its shores with a belt of altars dedicated to the gods. In like manner the tradition of the Deluge of Ogyges seems connected with the recollection of an extraordinary rise of the Lake Capaïs, inundating the whole of the great Bœotian Valley, a recollection amplified later--as is ever the case with legends--by applying to the local disaster all the details popularly told of the primitive Deluge which had taken place before the separation of the ancestors of the two races, Semitic and Aryan. It is also probable that some event that had occurred in Thessaly, or rather in the region of Parnassus, determined the localization of the legend of Deucalion. Nevertheless, it always retained, as we have seen, a more general character than the others, whether the Deluge be extended to the whole earth or limited to the whole of Greece. Be that as it may, the different narratives were reconciled by admitting three successive Deluges, those of Ogyges, Deucalion, and Dardanos. The general opinion pronounced the former the most ancient, placing it 600 or 250 years before that of Deucalion. But this chronology is far from being universally accepted; and the inhabitants of Samothracia maintain their Deluge to have been the earliest. Christian chronographers of the third and fourth century, as, for instance, Julius Africanus and Eusebius, adopted the Hellenic dates of the Deluges of Ogyges and Deucalion, and inscribed them in their records as different events from the Mosaic Deluge, which, for their part, they fixed at 1000 years before that of Ogyges.