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plates were so eaten through as to require doubling or renewal. Similar effects are often produced by the contact of copper pipes or roses with imperfectly protected bottom plating. This all shows the necessity of both frequent and careful surveys.
The loss of the La Plata and narrow escape of the Amérique exemplify the danger arising from insufficient control of sea-cocks ; such dangers however are much less in vessels of more recent construction where it is usual to place all sea-cocks above the stokehole platform, where they are in sight.
The pumping arangements, especially in cases of vessels with water ballast, have not in the past been thoroughly efficient; it is desirable that they should be such as to enable the holds and tanks to be pumped out when the vessel is inclined, and all guction pipes should be capable of connection with the bilge pumps to main engines, and donkey pumps also.
Steamers of recent design built to carry cargo only, are much more dependent upon their engines than those of former types were, they have but small sail power, they are of unhandy form, and the propeller remaining immersed, is a cause of their steering badly when under sail. For these reasons, much greater care should be taken in the examination of all the details of the engines when in port than often is the case. The common arrangement of steering from the bridge amidships also introduces an element of danger in the complicated rods, chains, and sheaves necessary for that purpose.
Bad navigation is a common cause of loss, but probably the large increase of the value of shipping property committed to the charge of shipmasters of late years, bas been met by increased efficiency on their part.
Having thus dealt with some of the causes of losses of comparatively new ships at sea, Mr. Martell goes at greater length into the remaining divisions of his subject. He thinks that due importance is not yet attached to the provision of proper protection for the various deck openings, and says :-"From want of due precaution in this, and in failing to provide proper coverings for stoke-holes and fastenings for coal bunkers, pipes or hatches, many losses I feel certain have occurred. When we hear of the
funnel and ventilators being washed away in some of our largest passenger steamers, with decks ten or twelve feet above the water, what are we to expect if proper attention is not given to these vulnerable parts in deeply-laden cargo ships, with a freeboard in some cases not exceeding four feet ? ”
The employment of steamers for cargo-carrying alone, began on the North-east coast for the carriage of coals coastwise. Extreme fulness of form and flat floor were desirable for this trade, and when steamers were built for the Baltic, and afterwards Mediterranean trade, these characteristics were retained, partly from the mistaken notion that the less the area of amidship section, the less the propelling power required for a given speed on a given displacement. A flat floor gives a less draught for a given displacement, enables the engines and boilers to be placed low, and, combined with full ends, gives greatest cargo under the same principal dimensions. The double-bottom throughout the holds also may be traced to the requirements of the coal coasting trade. The design of the flash-deck coasting collier has developed through the stages of raised quarter-deck and monkey-forecastle, short poop, bridge-house, and forecastle, long poop, spar-deck, to the final type of three-decked steamer with full scantlings to upperdeck. Comparing these classes of vessels as regards their stability, Mr. Martell gives the result of calculations in a selected case of each type, showing that when loaded with a full cargo of coals or grain, the spar-deck vessel loaded so that her main-deck is above water, is very superior to all the others as regards stability, and the three-deck ship loaded deep is by far the worst. Even with a small initial stability the spar-deck vessel with the large freeboard has a large righting force when on her beam-ends, as was exemplified in the case of a vessel of this kind in 1977, abandoned in the Bay of Biscay, and although the cargo shifted, she was rolling about for three days in a heavy sea and did not capsize. The effect of deep loading is shown by the fact that in one calculated example an increase of stability is obtained by a foot more freeboard, greater than if the vessel's beam had been increased two feet. The conclusion arrived at is that three-deck ships of the existing type should, to ensure their stability, bare
more freeboard, and that in vessels of this class built in future it is desirable to increase the beam. It must, however, be remembered that rapid dispatch has been so much aimed at as often to be the occasion of bad stowage, and without good stowage the best designed ship may be unsafe.
Mr. Martell next deals with the question of double-bottoms and water-ballast, briefly adverting to the absurd, popular notion that the air in the ballast-tank causes it to act like a balloon. Ballasttanks are a commercial necessity; in some vessels where they are fitted, a cargo of light coal or grain in connection with an empty ballast-tank gives deficient stability ; in such cases a compartment of the tank might be filled with water, this would make a very great difference in the stability.
A much better kind of vessel than the three-deck ship would come into existence if the awning-deck or spar-deck were not charged as much for tonnage dues as they are at present. The ’tween-deck space gives great safety to the ship, but earns no freight, and yet has to pay as much as if the whole ship were loaded to the upper-deck, and consequently loaded two or three feet deeper. Either the space actually occupied by cargo in the 'tween-decks should be measured or a deduction made from the gross space. In other ways the tonnage laws have a prejudicial effect upon the Mercantile Marine ; in the case of high coamings, their measurement in the tonnage tends to discourage an obvious good. So with the protection of the engine and toiler openings, the tonnage laws encourage the bridge space with open passage ways. A complete bridge-house with water-tight doors would be a much safer and better arrangement.
Coming to the much-discussed question of grain cargoes, a considerable improvement was effected for some few years after 1872, a period when public attention was first directed to the subject. In Montreal the Port Warden has powers over the loading; in 1873 the fine for non-compliance with his regulations was increased from $40 to $800," and since that time not a single grain-laden vessel from the port of Montreal has foundered at sea.” Grain loaded in bulk by means of elevators is usually from the nature of the case imperfectly trimmed, and as a consequence the
settling is very much more than is usually allowed for. Shifting boards as often fitted, only three to four feet below the beams, are useless in the face of this consideration. When steamers of 1,200 to 1,800 tons are loaded within ten hours, as is often the case in American ports, it may be expected that the grain is not properly trimmed, and this accounts for the very great amount of settling often now observed.
Considering different types of vessels in regard to the carriage of grain, there is first the case of the vessel with one deck carrying grain so light that she might be filled without being overladen. With proper shifting boards and due care in trimming and pressing down the grain in the wings, this vessel might be loaded so as to be safe ; or better still, the hold might be filled to within a few feet with grain in bulk, then filled up with grain in bags resting on boards. The shifting boards should extend to keelson. If a ship of this kind has to carry grain, which is too heavy to allow of her hold being filled with it, it is better to bulkhead off portions of the hold, so that where the grain is carried it should reach as nearly as possible to the deck. Such temporary bulkheads have often not been made strong enough to ensure efficiency.
Taking next the case of vessels with a lower deck laid, carrying light grain, it may be determined to make the lower-hold arrangements complete in themselves, as in fact in the case of the vessel with one deck, or a plan may be adopted for feeding the lower hold from the 'tween-decks as the grain settles. Either plan may be made efficient if properly carried out. It would appear desirable not only to have openings in the lower-deck for feeding at the middle line, but also at the sides, it being by no means certain that grain let down through the middle-line hatches will find its way to the wings. In the case of a vessel of this kind carrying heavy grain, it is necessary to combine with artangements for feeding, such bulk-heading of the 'tween-decks as to shut off empty compartments in order that the spaces holding grain may be as nearly as possible filled. Mr. Martell thus concludes this part of
his paper :
“I cannot, however, pass from this question of grain-loading without a word on the proposal to carry all the grain in bags.
This is a question that is now receiving investigation by a Select Committee of the House of Commons, who will, I doubt not, arrive at a sound conclusion on the subject. That it would be more expensive there cannot be a doubt, and my enquiries have led me to the conclusion that this would amount, in an American voyage, to about 8 d. per quarter, or say £360 per voyage in a vessel of about 1,200 tons nett register, including the cost due to delay in loading. That a cargo composed partly of bulk and Partly of bag grain can be made as safe as a cargo containing all bags, is a question on which all practical men are agreed.” The figures in the Table of Losses show that as many coal-laden as grain-laden steamers have been lost during the past winter. There is further the difficult subject of overloading. This is responsible for many losses. It is hoped that if attention be called to it, so as to show its great evils, further good may result. It is a decreasing evil.
In the discussion which followed the reading of this paper, Mr. Merrifield advocated a system by which a vessel's stability should be always calculated, so that the shipmaster should be aware of the character of his ship. At the same time the shipmaster should exercise more intelligence in supervising the loading.
Mr. Scott Russell thought that ships should be more effectually divided into compartments than at present; especially there should be a fore-and-aft bulkhead at the middle line. It would be better to carry the water-ballast in special compartments of the hold rather than in tanks as at present fitted.
Mr. Denny pointed out that an expenditure of a few hundreds a-year by the shipbuilder in obtaining information on the stability of ships built by him would be well laid out. With reference to greater beam, it was the case that while Mr. Martell was in favour of it, Lloyd's rules acted against it, for, by causing the longitudinal strength to be regulated by the breadth, depth, and half-girth of the midship section, the tendency was to increase improperly the scantlings of plates, &c., when the beam was increased.
Mr. John, in reference to the effect of the water-ballast tank apon stability, said that, making allowance for dunnage, the real listing of the cargo was but one foot. Contrasting a merchant