Indeed, when we think of it, we are led to conclude that this must necessarily be the case. There are, as we shall presently show, currents of vast size and enormous power constantly flowing through the ocean; and when we think of the tremendous power of running water to cut through the solid rock, as exemplified in the case of Niagara, and many other rivers, what would be the result of the action of currents in the sea, compared with which Niagara is but a tiny rivulet? Ocean currents, then, flow on a bed of still water, that protects the bottom of the sea from forces which, by calculation, we know would long ago have torn up the foundations of the deep, and would probably have destroyed the whole economy of nature, had not this beautiful arrangement been provided by the all-wise Creator.

Chapter Three

Waves—System in all Things—Value of Scientific Knowledge—Illustrative Anecdote—Height of Waves—Dr Scoresby—Size, Velocity, and Awful Power of Waves—Anecdotes regarding them—Tides

When a man stands on the deck of some tight-built ship, holding on to the weather bulwarks, and gazing with unphilosophic eye through the blinding spray at the fury of the tempest—by which the billows are made to roll around him like liquid mountains, and the ship is tossed beneath him like a mere chip, the sport and plaything of the raging waters—he is apt to think, should his thoughts turn in that direction at all, that all is unmitigated confusion; that the winds, which blew west yesterday and blow east to-day,—shifting, it may be, with gusty squalls, now here, now there, in chaotic fury,—are actuated by no laws, governed by no directing power.

Yet no thought could be more unphilosophical than this. Apart altogether from divine revelation, by which we are informed that “all deeps, fire, and hail, snow, and vapour, and stormy wind,” are “fulfilling God’s word” (which information we are bound to receive as a matter of faith if we be Christians, and as a matter of necessity if we be men of common sense, because it is mere absurdity to suppose that the “stormy winds,” etcetera, are not fulfilling God’s word—or will), we now know, to a great extent from practical experience and scientific investigation, that the winds blow and the waters of the ocean flow in grand, regular, uninterrupted currents. Amongst these there are numberless eddies, which, perhaps, have tended to fill our minds with the idea of irregularity and confusion; but which, nevertheless, as well as the grand currents themselves, are subject to law, and are utterly devoid of caprice.

In regard to these matters there is much about which we are still in ignorance. But the investigations of late years—especially those conducted under the superintendence of Captain Maury of the American Navy, and Doctors Carpenter and Thompson of England—have shown that our atmosphere and our ocean act in accordance with a systematic arrangement, many facts regarding which have been discovered, and turned, in some cases, to practical account. See Note 1.

A very interesting instance of the practical use to which scientific inquiry can be turned, even in its beginnings, is given by Maury. After telling us of the existence and nature of a current in the ocean called the Gulf Stream, he gives the following account of the manner in which upon one occasion be made use of his theoretical knowledge.

In the month of December 1853, the fine steam-ship San Francisco sailed from New York with a regiment of United States troops on board, bound for California by way of Cape Horn. She was overtaken, while crossing the Gulf Stream, by a gale of wind, in which she was dreadfully crippled. Her decks were swept, and, by one single blow of those terrible seas that the storms raise in the Gulf Stream, more than in any other part of the Atlantic, one hundred and seventy-nine souls, officers and soldiers, were washed overboard and drowned.

The day after this disaster she was seen by one vessel, and again, the next day, December 26th, by another; but neither of them could render her any assistance.

When these two vessels arrived in the United States and reported what they had seen, the most painful apprehensions were entertained by friends for the safety of those on board the steamer. Vessels were sent out to search for and relieve her. But where should these vessels go? Where should they look?

An appeal was made to know what light the system of researches carried on at the National Observatory concerning winds and currents could throw upon the subject.

The materials they had been discussing were examined, and a chart was prepared to show the course of the Gulf Stream at that season of the year. Two revenue cutters were then appointed to proceed to sea in search of the steamer, and Maury was requested to “furnish them with instructions.”

It will be observed here that the gentleman thus appealed to was at the time engaged in his study at Washington, utterly ignorant of all that had occurred within the previous few weeks on the stormy Atlantic, except through the reports brought thence by ships. These reports furnished him with meagre data to proceed upon—simply that a crippled steamer had been seen in a certain latitude and longitude on a particular day.

But this information was sufficient for the practical man of science. Proceeding upon the supposition that the steamer had been completely disabled, he drew two lines on the chart to define the limits of her drift. This his previous knowledge of the flow of the Gulf Stream at all seasons of the year enabled him to do. Between these two lines, he said, the steamer, if she could neither steam nor sail after the gale, had drifted. And that she could neither steam nor sail he had good reason to suppose from the account of her brought in by the vessels above mentioned. A certain point was marked on the chart as being the spot where the searching vessels might expect to fall in with the wreck.

While these preparations were being made, two ships fell in with the wreck and relieved the crew. This, however, was not known at the time by the anxious friends on shore. The cutters sailed on their mission, and reached the indicated spot in the sea, where, of course, their assistance was now unnecessary. But when the vessels that had relieved the crew of the wreck arrived in harbour and reported where the wreck had been last seen, it was found to be within a few miles of the spot indicated by Maury!

Thus, upon very slight data, a man of science and observation was enabled, while seated in his study, to follow the drift of a wrecked vessel over the pathless deep, and to indicate to a rescue party, not only the exact course they ought to steer, but the precise spot where the wreck should be found.

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