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have not been considered and appreciated. One of the old traditions: of the shipbuilder has been that no moveable dead-weights should be on board the ship at the time of the launch. In the hurry and bustle of modern competition this old maxim has been disregarded very frequently, and long immunity from accident has tended to perpetuate neglect of the old precautions. Similarly the specially dangerous condition of vessels in the extreme light condition has been well understood, and every shipmaster knows that a crank vessel when very light may completely capsize under conditions where an equally crank loaded ship would simply take a list and remain permanently inclined at a moderate angle. We cannot grant that the mere enunciation in scientific terms of a previously well-known fact is of itself a scientific discovery.
In looking about for possible causes of the disaster, various suggestions were made by actual observers and others, which were all carefully considered by the Commissioner. One was that there is in the River Clyde, at certain states of the tide, an up current above at the same time that there is a down current beneath. This suggestion being considered in connection with the evidence of the engineer to the Clyde Trust, was dismissed as not being in accordance with the observed facts of the case. It was further suggested that in the launching of a ship after she has lost the support of the ground-ways, and before she is wholly waterborne, there is a passing phase of instability. This view was advanced by M. Benjamin Normand, of Havre, and in reply it is urged with justice that “the duration of this state of things is so brief, that it can hardly have any greater effect than that of setting up some little inclination, which probably accounts in part for the occasional slight rolling of a ship after launching. No doubt the passing phase of instability which the just-launched ship may momentarily experience is deserving of consideration, especially when other circumstances co-operate with it, but where the ship was well launched as the Daphne was, and takes the water with a proper velocity as she did, its effect is in my judgment too small and too transient to furnish the necessary force for capsizing the ship.” .
While thus disposing of these suggestions as to the cause of the capsize, and at the same time coming to the conclusion that
the vessel had a metacentric height of four inches, Sir Edward Reed does not in his report make any suggestion as to what was the actual inclining force. It would appear that but a very small force was necessary because there were elements of danger in the vessel in the shape of weights which, given an inclination of moderate amount, would move to leeward, and would be sufficient to use up all the righting power of the ship. On this point it is said :-" I have made numerous calculations showing what changed conditions would exist upon various assumptions as to weights moved; but although there were over 30 tons of loose weights (including men) on board, I will content myself with assuming that only 15 tons moved across the decks and holds, through an average distance of 15 feet-a moderate assumption. This, however, would have sufficed to incline the ship permanently at an angle of over 30 degrees from the upright, and in carrying her over to that angle would have accumulated sufficient work to nearly, but not quite absorb, the remaining stability. The vessel would, on this assumption, have ceased to roll over, and even have returned slightly towards the upright position ; but it is not to be expected that the vessel was watertight up to the top deck; indeed, it is certain that she was not, and that some water found its way on to the main deck, and this fact, taken together with the further shifting of weights, which would occur at so large an inclination, would cause her to be carried over again. At 501°, the water would flow over the bulwarks, and complete the capsize.” With the state of things thus, described, it is evidently not necessary to go far to seek the cause of a small primary inclination, from which the capsize would inevitably result. Whether such a cause might be found in the action of the water upon the propeller, in the effect of the vessel being brought round in the water by the drag-chains, or by the action of waves set up by the sudden displacement of water in a narrow river, is obviously only of secondary importance. The lesson to be learnt is, that the special dangers connected with launching must be provided for by proper ballasting, by the securing of all heavy articles on board, and by strictly limiting the number of persons in the vessel during the launch.
The question of stability, however, as concerning launching is obviously of much less importance than the larger one opened up by Sir Edward Reed in his remarks upon the general question. On this point he says :—“The general belief that a high-sided ship having some initial stability will, as she inclines, gather additional stability, and will retain some even at very large angles, has exercised a widespread influence upon modern mercantile shipbuilding, and has greatly encouraged people to be satisfied with very small initial stability, in some cases with nope at all, and even less than none. Many steamships of large tonnage have been built of late years, for influential steam companies and other owners, which ships are wholly incapable of floating upright without the aid of ballast or of cargo, and which cannot be unloaded in dock without being held upright by hawsers attached to the shore. Such ships, even when capable of floating unballasted without capsizing, can only do so by lolling over at large angles of inclination, and there finding a position of stable equilibrium. When carefully watched over, and stowed with suitable cargoes, these ships can usually be made safe at sea, and sometimes even safer than ships with larger initial stability but less rangea circumstance to which undue prominence has perhaps been given, and which has diverted many from the grave elements of danger which much more often are associated with small initial stability."
We have in these pages more than once protested against the undue importance which has of late years been attached to range of stability in merchant ships. Just as large initial stability must to secure safety be associated with proper range, so large range will not make up for deficient metacentric height. There is always some part of the cargo or coals which can shift, and with small initial stability the vessel gets a list, and if in that condition she meets with bad weather, the consequence is disaster.
Further, the very proportions which conduce to small metacentric height are those which tend to secure large range, so that. if, in answer to a charge of crankness against a ship, the plea is. made that she has large range, it is much the same thing as directly admitting the defect.
One reason for the existence of many vessels of low initial stability is found in the notion now exploded that speed depended largely upon smallness of beam. The last few years have seen a beneficial change in the proportion of beam to depth, and a better state of things as regards stability, especially in the case of vessels built for cargo rather than passengers. In many of the largest ocean steamers, the proportions even of new vessels are against their stability, but in their case, owing to the diversified character of the cargo, and in some cases to the existence of well-divided ballast tanks, it is easy to keep the actual stability of the ship under control. Such vessels, too, in regular trades are stowed voyage after voyage by the same stevedore, and thus there is every opportunity of correcting the stability by proper stowage.
In commenting upon the question of the stability of merchant vessels, Sir Edward Reed made some remarks which appeared to indicate that the importance of that question was imperfectly appreciated in enquiries into losses at sea. The Wreck Commissioner has since pointed out that this is not the case, and it is understood by a subsequent explanation that the reference was rather to the fact that evidence is not forthcoming as to stability than that the question is not considered. It has been the usual practice in these enquiries for the Board of Trade to call evidence as to fact, the Court being constituted so as to form its own opinion by the aid of nautical or scientific assessors. Evidence as to stability is difficult to obtain, because owners do not think the information of sufficient value to induce them to get it in the first instance. After the ship is lost her conditions of stability may be obtained approximately from the drawings, but it is obvious that such information got up for the purpose of evidence is less valuable than an exact account of the vessel's stability got out by experiment for use in loading her. It is only just to the Wreck Commissioner to point out that in enquiry after enquiry he has directed attention to the question of stability, and has as often expressed his regret that shipowners did not make it their business to obtain exact accounts of the stability of their ships.
In the Austral enquiry, it certainly appeared that the scientific aspects of the case were pushed so far as to put out of sight the plain and simple causes of the accident. The crude notion of the Wreck Commissioner that the metacentric curve for various immersions and curves of stability at the light and load draught could be placed in the hands of the shipmaster who, with a little reading up on the subject would be able by their means to regulate the stowage and ballasting of his vessel, needs only to be stated for both naval architect and sailor to perceive its futility.
The fact must not be lost sight of that the intelligent shipmaster does know very much about stability, if he does not know what the metacentre means; that if he cannot calculate the exact metacentric height from an experiment, such as would be made by the naval architect, he can and does make experiments of his own. As soon as the vessel gets clear of port, he knows whether she is too stiff or too crank ; and if he is in any doubt he can set a topsail and notice its effect. After one or two voyages, he knows how his vessel should be stowed and what ballast is necessary either to shift her in port or to take her to sea. If he does not dare to put back when he knows his ship to be crank, that is quite another matter, and indicates a relation between himself and his employers for which a remedy must be sought in some other direction. Put the information which the shipmaster already has into scientific form, before you have thoroughly taught him to read the language of science, and you simply confuse him ; he is led to forsake the little bit of firm ground on which he stood, to flounder in a quicksand. Now, it is quite certain that the average shipmaster cannot be made a scientific naval architect, nor can he hope to master the whole question of stability. Such a hope would indeed appear to be altogether vain in view of what we are told in the Daphne report, that on a most important part of the question numbers of naval architects and even writers of standard works on naval architecture have accepted erroneous views which will not for a moment stand the test of scientific investigation, and which, as soon as they are carefully considered, are seen to be wrong. If what is thus said is to be taken as it stands, the retort is obvious :—“Before you presume to teach us (the shipmasters) how to stow and manage our ships, make sure of your own position ; better be ignorant as we are, than spend time and trouble in acquiring learning ; which, after all, may not be knowledge of fact, but only imagination.” The truth is,