The supposed origin of the Bosphorus is connected with the most awful phenomena of nature; and the lovely strait, which now combines all that is beautiful and romantic, grateful to the eye, and soothing to the mind, owes its existence to all that is fearful and tremendous.−-At its eastern extremity, and above the level of the Mediterranean, there existed an inland sea, covering vast plains with a wide expanse of waters, several thousand miles in circumference. By a sudden rupture, it is supposed, an opening was made, through which the waters rushed, and inundated the subjacent countries. For this supposition there are strong foundations of probability. The comparatively small sheets of water now partially occupying the space which the greater sea once covered, under the names of the Euxine, Azoph, Caspian, and Aral seas, are only the deeper pools of this great fountain, which has, in a succession of ages, been drained off, leaving the shallower parts dry land, with all the marks of an alluvial soil. The spot where the great rupture is supposed to have taken place is indicated by volcanic remains: basalt, scoriæ, and other debris of calcination, lying all around. The strait itself bears all the marks of a chasm violently torn open, the projections of one shore corresponding to the indentations of the other, and the similar strata of both being at equal elevations, while the bottom is a succession of descents, over which the water still tumbles with the rapidity of a cataract. The opinions of antiquaries accord with natural appearances. The first land which this mighty inundation encountered was the continent of Greece, over which it swept with irresistible force. Tradition has handed down to us the flood of Deucalion; and ancient writings have assigned as its cause, “the rupture of the Cyanean rocks:” so that both poets and historians concur in preserving the memory of this awful event. After the first effects of this inundation had ceased, a current was still propelled by the Danube, the Borysthenes, and other great rivers, which pour their copious streams into the Euxine, and have no other outlet: hence it still runs down with considerable velocity. In some places, where the convulsion seems to have left the bottom like steps of stairs, this is dangerously increased. It is possible that the continued attrition of the water, for thousands of years over this rocky surface, has worn it down to a more uniform level; still three cataracts remain, one is called _shetan akindisi_, or “the devil’s current:” it is necessary, from its laborious ascent, to haul ships up against it with considerable toil. To the ancients it was accounted a perilous navigation, when the broken ledges were still more abrupt. Among the acts of daring intrepidity was deemed the navigation of this strait. Hence Horace says−- “To the mad Bosphorus my bark I’ll guide, And tempt the terrors of its raging tide.”