Contemporaneously with this phenomenon, another, and even more wonderful one appeared. This was a succession of tide-rips, so remarkable, that they deserve special description.
The _Sumter_ lay nearly stationary, during the whole of these phenomena--the easterly current setting her back, nearly as much as she gained under sail. She was in the average latitude of 5° N., and average longitude of 42° W. For the first three days, the rips appeared with wonderful regularity--there being an interval of just twelve hours between them. They approached us from the south, and travelled toward the north. At first, only a line of foam would be seen, on the distant horizon, approaching the ship very rapidly. As it came nearer, an almost perpendicular wall of water, extending east and west, as far as the eye could reach, would be seen, the top of the wall boiling and foaming, like a breaker rolling over a rocky bottom. As the ridge approached nearer and nearer, it assumed the form of a series of rough billows, jostling against, and struggling with each other, producing a scene of the utmost confusion, the noise resembling that of a distant cataract. Reaching the ship, these billows would strike her with such force, as to send their spray to the deck, and cause her to roll and pitch, as though she were amid breakers. The phenomenon was, indeed, that of breakers, only the cause was not apparent--there being no shoal water to account for it. The _Sumter_ sometimes rolled so violently in these breakers, when broadside to, that we were obliged to keep her off her course, several points, to bring the sea on her quarter, and thus mitigate the effect. The belt of rips would not be broad, and as it travelled very rapidly--fifteen or twenty miles the hour--the ship would not be long within its influence. In the course of three quarters of an hour, it would disappear, entirely, on the distant northern horizon. So curious was the whole phenomenon, that the sailors, as well as the officers, assembled, as if by common consent, to witness it. "There come the tide rips!" some would exclaim, and, in a moment there would be a demand for the telescopes, and a rush to the ship's side, to witness the curious spectacle. These rips have frequently been noticed by navigators, and discussed by philosophers, but, hitherto, no satisfactory explanation has been given of them. They are like the bores, at the mouths of great rivers; as at the mouth of the Amazon, in the western hemisphere, and of the Ganges, in the eastern; great breathings, or convulsions of the sea, the causes of which elude our research. These bores sometimes come in, in great perpendicular walls, sweeping everything before them, and causing immense destruction of life, and property. I was, at first, inclined to attribute these tide rips to the lunar influence, as they appeared twice in twenty-four hours, like the tides, and each time near the passing of the meridian, by the moon; but, in a few days, they varied their times of appearance, and came on quite irregularly, sometimes with an interval of five or six hours, only. And then the tidal wave, for it is evidently this, and not a current, should be from east to west, if it were due to lunar influence; and we have seen that it travelled from south to north. Nor could I connect it with the easterly current that was prevailing--for it travelled at right angles to the current, and not with, or against it. It was, evidently, due to some pretty uniform law, as it always travelled in the same direction.