Early in the course of the following month, the Great Eastern sailed from the Mersey on her fourth Transatlantic voyage with 400 passengers of different classes for New York. On this occasion she encountered, on the 12th and 13th of September, a heavy gale of wind when about 280 miles off Cape Clear, and sustained so much damage that she was obliged to put back and seek shelter in Cork Harbour. Various accounts of this disaster appeared, at the time, in the daily journals. Her paddles, it would appear, were seriously injured, and her rudder “rendered useless.” Nor do the writers of these accounts speak very highly of the anticipated superior sea-going qualities of the great ship, or of her freedom from that violent motion in a gale, to which ordinary vessels are subjected. Indeed, one of her passengers on this occasion, in a letter he addressed to the Times, gives the most melancholy account of her, but this description of the disaster and the imminent danger to which her passengers were exposed, is probably exaggerated.[434] Landsmen in a gale, especially when anything goes wrong, generally, take the most gloomy view of matters; they picture to themselves dangers which have no reality, and, when they see the seamen hurrying to and fro to rectify, as far as possible, any damage the ship may have sustained about her spars, rigging, or bulwarks, they too frequently give themselves up for lost.
So long as the hull of a ship keeps sound the action of the ocean, however disturbed, does not, materially, affect her safety, but, in this action, the landsman, too frequently, sees just that kind of danger which the sailor is said to have dreaded during a gale on land, from falling slates and broken chimney-pots, congratulating himself that he was at sea and not on shore in the midst of the storm.
General remarks on the sea-going qualities of different ships,
On the other hand, the anticipated ease and safety of the Great Eastern during a gale was about as much exaggerated, as the discomforts and danger the narrator of the gale has described. One enthusiastic writer, among numerous others equally sanguine, in his description of what might be expected from the great ship in a storm, remarks “she will set circular sailing at defiance,” as if circular sailing has anything whatever to do with the sea-going qualities of a vessel. He then exclaims: “The line which in a tornado is said to make a steady but resistless run of 20 miles will be counteracted by the ‘wave line,’ which Mr. Scott Russell has adopted as the principle on which she has been built. Storms and tempests will be looked upon as merely sublime phenomena, in nowise menacing peril as things scarcely affecting the ship, but to be gazed upon out of snug cabin windows as interesting episodes of the voyage.”
and on the effect of wind in causing “rollers.”
So much for the two extremes, but from these glowing anticipations on the one hand, and the exaggerated account of the actual event on the other, some lessons may be learned. The wave line (whatever may be its advantage, if any, over the lines usually adopted by shipbuilders) can produce no sensible difference in the violent motions of a ship at sea, even if it tends to promote greater speed. Waves are of greater length and height, according to the force of the gale and its extent of sweep over the ocean.[435] In channels, where broken by projecting points of land or promontories, they are short and disturbed. When crossing the whole breadth of the Atlantic during a westerly gale, they are long, and, as they roll between the headlands forming the Bay of Biscay, they are also disturbed, rendering a voyage across that part of the ocean a proverbially unpleasant and, with deeply laden and badly found ships, a somewhat dangerous one. To insist, therefore, as some writers appear to have done, that the lines of a ship should be in conformity with the length and action of the waves, or that, by a careful study of the law of fluids, they can be so drawn as to render, under all the varied circumstances of a long voyage, one ship more easy or even more swift than another, is, I fear, attributing to science more than it can reasonably claim; for though, by its general application to the models of ships, great improvements have of late years been made, I can hardly suppose that lines, based on the action of fluids, which must be more or less disturbed by the weight and velocity of a vessel passing through them, and by the action of the winds on their surface, do really possess any superior advantages so far as regards greater ease, speed or safety.[436]
Nor had the idea, which prevailed at the time, that a ship of the vast dimensions of the Great Eastern would bid defiance to the danger of the ocean, much more foundation in fact. No doubt a vessel of 1000 tons is a much safer mode of conveyance across the Atlantic than one of 100 tons, and a vessel of 2000 tons may be still more so, but not to either the same degree or extent. Moreover, a ship of double that size, or say 4000 tons, is no safer, though she may be more comfortable, for various self-evident reasons, such as being less liable to receive on deck the crest of the waves, or by affording more space and better ventilation in her cabins; but anything beyond that size will, assuredly, not realize much greater speed, though she may afford greater comfort.
Real truth about “momentum.”
A vessel of 100 tons is lifted by every large wave, and, consequently, the distance she has to traverse is increased. As the size is enlarged this particular description of motion diminishes, in proportion to the length of the vessel. But there is a limit to this advantage, as there is to most other things, and a vessel of 5000 tons and 400 feet long, will be, similarly, borne on the crest of two or more of the largest waves as a vessel 700 feet in length, and, therefore, would lose nothing in speed from the ascending and descending motions: this fact has, indeed, been satisfactorily proved, as the ships of the Ismay, Cunard, Inman, Allan, and other lines of steamers employed in Transatlantic voyages have made more rapid passages than ever the Great Eastern did.[437] Speed, beyond a certain size, is determined by the model, and the power of propulsion, due regard being had to the weight to be propelled and the resistance offered by the depth and extent of immersion. The momentum, about which a great deal was said and from which so much was expected in the case of the Great Eastern, though of some importance, when vessels of 100 tons are compared with those of 1000, is of much less consequence in the case of vessels of unusual weight and dimensions. It is at best only transitory, while, to drive a vessel of 20,000 tons through the water at the rate of 15 miles an hour, somewhere about four times greater power would be necessary than to secure the same speed in a vessel similarly constructed, of 5000 tons, although less power in proportion to tonnage would suffice in smaller vessels.
Very large ships not so safe as smaller ones, as their damages are less easily repaired.