The Bristol Channel and the bay of St. Malo in Brittany, are also renowned for their high tides. Near Chepstow, the flux is said sometimes to reach the surprising height of seventy feet, and at St. Malo the floods frequently rise to forty and fifty feet. When the water is low, this small sea-port town appears surrounded on all sides by fantastically shaped cliffs covered with sea-weeds and barnacles. Pools of salt water interspersed here and there among the hollowed stones, or on the even ground between them, and harbouring many curious varieties of marine animals, are the only visible signs of the vicinity of the ocean, whose hoarse murmurs are heard resounding from afar. But an astonishing change takes place a few hours after, when the town, surrounded by the sea, would be a complete island, but for a long, narrow causeway called "_the Sillon_," which connects it with the mainland. On the side fronting the open sea, the tide breaks with tremendous rage against the strong buttresses that have been raised to oppose its fury, rises foamingly to a height of thirty or forty feet, and threatens the tardy wanderer as he loiters on the narrow causeway. The cliffs that erewhile were seen to surround the town are now hidden under the waters, some few excepted, that raise their rugged heads like minute islands above the circumambient floods. The opposite side of the causeway is also washed by the sea: but here its motions are less tumultuous, for after having broken against numberless rocks and made a vast circuit, it scarce retains a vestige of its primitive strength. On this side lies the vast, but deserted harbour of St. Malo, completely dry at ebb-tide; a wide sea during the flood. Two eminent French authors, Chateaubriand and Lamennais, were born at St. Malo, and there can be no doubt that the imposing spectacle I have briefly described must have greatly contributed to the widening of their intellectual horizon. Daily witnesses from their early childhood of one of the grandest phenomena of nature in all its wild sublimity, the boundless and the infinite soon grew familiar to their mind, enriching it with splendid imagery and bold conceptions. Although the sun and the moon exert some attraction upon the smaller and inclosed seas, yet the development of a powerful flood-wave necessarily requires that the moon should act upon a sufficiently wide and deep expanse of ocean. Even the Atlantic is not broad enough for this purpose, as its equatorial width measures no more than one eighth of the earth's circumference: and the Pacific itself, notwithstanding its vast area, is so studded with islands and shallows, that it presents a much more obstructed basin for the action of the tide-wave than might be expected, from its apparent dimensions and equatorial position.