Impetuous is the channel where her strait receives the full rush of the North sea, and very turbulent is the sea of Brittany, rushing over basaltic shoals in swift and furious rapids. But the gulf of Gascony, from Cordouan to Biarritz, is just one long maritime contradiction, one enigma of mighty strifes. As she goes to the southward, she suddenly becomes extraordinarily deep, as though her waters sank, on the instant into some vast and fathomless abyss. Passing over that sudden and immense depth, the onward wave under the impulse of the terrible pressure leaps upward to a height and onward with a velocity unequalled by any other of our seas. The great surge from the north-west is the motive-power of this huge liquid machinery; from a little more north it threatens to crush Saint-Jean-de-Luz; farther west it repels the Gironde, and crowns with her terrible billows the luckless Cordouan. That poor Cordouan, that respectable martyr of the seas and victim of the tempests, is only too little known. I believe it is the oldest of all the European beacons. At all events, only one, the celebrated Genoese lantern, can rival it in antiquity. But there is a vast difference between them. The Genoese, crowning a fort and solidly seated upon solid rock, looks smilingly, almost scornfully, down upon the impotently furious storms. But Cordouan is upon a shoal which the water never wholly leaves. And, in truth, he was a bold man who conceived the notion of erecting a beacon here, amidst the waters; what say I? in the eternal wave-combat between such a river and such a sea. From one or the other, it, at every instant, receives tremendous blows. Yes, even the Gironde urged on the one hand by the winds, and on the other by the rude torrents from the Pyrenees, assails this stern calm guardian, as though it were responsible for the assailing and repelling fury of the ocean. Yet, Cordouan is the only saving and consoling light that gleams over this stormy sea. Run before the north wind, and miss Cordouan, and verily, my storm-tossed brother, you are in very real danger; you, likely enough, will fail to sight Arcachon. This sea, most stormy among seas, is also the darkest. At night, storm-driven upon that sea, there is no guiding mark, if you miss the beneficent light.