Tonnage of Wooden Vessels registered in the United Kingdom which were Lost, Broken up, &c., during each of the years 1879 to 1883, with Tonnage of Wooden Vessels built and registered in the United Kingdom during the same period.
| Year. | Tonnage of Wooden Vessels. | Excess of Vessels lost over those built. | |
|---|---|---|---|
| Lost. | Built. | ||
| 1879 | 149,828 | 26,186 | 123,642 |
| 1880 | 173,065 | 19,938 | 153,127 |
| 1881 | 170,283 | 18,107 | 152,176 |
| 1882 | 166,809 | 14,850 | 151,959 |
| 1883 | 144,138 | 15,202 | 128,936 |
| Totals, | 804,123 | 94,283 | 709,840 |
Whence it appears that while 709,840 tons of the 1,779,112 tons of ships removed from the register during the last five years were wooden vessels, only 94,283 tons of the 3,667,144 tons built and registered in the United Kingdom during the same period were constructed of that material. In other words, wooden ships represent 45 per cent. of the total losses, while they only represent 2·5 per cent. of the total tonnage built and added to the register during the five years in question.
Just as the introduction or general adoption of the compound engine marked an epoch in the history of shipbuilding and marine propulsion, so now the introduction of “mild steel” or “ingot iron” as a material for shipbuilding, together with the more extended adoption of water ballast, and the rapid development of the continuous-cellular system of construction, may be said to constitute a fresh starting point in the history of the industry.
Although the introduction of steel as a material for shipbuilding dates at least as far back as 1860, its use has been but partial or occasional until within very recent times. The uncertainty as to quality, the frequent great disparity between pieces cut from the same plate, and the special care needed in the manipulation, prevented its general adoption. With the highly-improved “mild steel,” however, first manufactured in France, and applied to shipbuilding purposes there about nine years ago, and subsequently introduced into this country, began the more extended adoption of steel, which every day, or with every accession to experience, is displacing iron.
The facts relating to the introduction into this country of mild steel for shipbuilding purposes, may be briefly recounted. In the latter end of 1874, Admiral Sir W. Houston Stewart, Controller of the British Navy, and Mr N. Barnaby, Director of Naval Construction, availed themselves of the opportunity to observe and study the use of steel in the French dockyards of Lorient and Brest, where three first-class armour-plated vessels were then being built of steel throughout, supplied from the works at Creusot and Terrenoire. Mr Barnaby, at the meetings of the Institution of Naval Architects in March following, gave an account of his observations during this visit, and pointed out clearly and precisely to the steel-makers of Great Britain all the indispensable conditions which would have to be met and satisfied by steel for shipbuilding, so that it could be used with confidence in the construction of the largest vessels. Before the end of 1875, the Landore-Siemens Company was enabled to fulfil these conditions, and the Admiralty contracted with them to supply the plates and angles necessary for the construction of two cruisers of high speed—the Iris and the Mercury. The material involved in this contract was steel obtained by the Siemens-Martin process. Shortly after this the Bolton Steel Company was in its turn able to produce by the Bessemer process plates and angles, satisfying all the requisite conditions. The Steel Company of Scotland, Butterly Company, and other important works, also entered into the same business, and operations are still going on in various parts of the country connected with the formation of new works, and the perfecting of other processes.
The steel furnished by these different works, subjected as it has been to systematic and severe tests continually applied, is now possessed of the qualities of ductility, malleability, and homogeneity, which render its employment in shipbuilding not only permissible but highly desirable. Its good and reliable qualities have been admitted by the Constructors of the Navy, the Officers of the Board of Trade, of Lloyd’s, and of the Liverpool Registries, as well as by all the most competent authorities. The experience of all who have practical dealings with the material in the shipyard is that it entirely satisfies—even more than iron—all the requirements of easy manipulation. The confidence with which it can be relied on, as to its certain and uniform qualities, places it on a much higher level than the steel formerly manufactured; and its superiority over the best wrought-iron as regards strength and ductility renders it a highly preferable material.
While doubt exists, however, as to the adoption of steel for shipbuilding being commercially advantageous; there must be hesitancy on the part of shipowners and others concerned. Although, since its introduction, mild steel has been greatly reduced in price, the first cost of a steel ship is still somewhat over that of an iron one, even after the reduction in weight of material is made, which the superiority of steel permits of. It has been shown that, about two years ago, a spar-decked steamer, of 4,000 tons gross, built in steel, as against a similar vessel built in iron, entailed an excess in cost of £3,570. The advantages, however, which accrue from the change, both immediate and in the long run, make the gain clear and considerable. Steel ships have been built with scantlings reduced one-fourth or one-third, and in some early cases even one-half, from what would have been considered requisite had iron been employed. Some authorities, not unnaturally, questioned the wisdom of accrediting steel with all the qualities which make such sweeping reductions justifiable. Except in vessels for river or passenger service, however, this is much in advance of the reductions obtained in ordinary modern practice.
The reductions allowed in vessels built to Lloyd’s requirements—and it cannot be urged that this society is too reckless in concessions of this nature—are 20 per cent. in scantling, and 18 per cent. in weight. As it is impossible to adjust the scantlings of material to take the full advantage of these reductions, and further, as allowance has to be made for extra weight due to the continued use of iron in vessels of steel—for purposes not essential to structural character—the average weight-saving effected in practice is about 13 to 14 per cent. This represents, in the finished vessel, a clear increase of at least 13 per cent. in dead-weight carrying power. The gain obtained in general practice has been otherwise stated on good authority as 7 to 7½ per cent. of the gross tonnage.
In trades where there is constancy of dead-weight cargoes, this increase in dead-weight carrying power should speedily recoup the owners for extra first cost, and in the life-time of vessels generally, a clear pecuniary gain should result. In trades, however, where the cargo consists of measurement goods, the advantages are not so decided, for it may sometimes happen that before vessels have been loaded to their maximum draught the limits of stowage will have been reached. Even here, however, the steel vessel has the advantage of her iron rival; her hull is 13 per cent. lighter, and consequently may be propelled at a given speed with much less expenditure of power, and has the further advantage—often a very important one—of a shallower draught. This latter consideration alone, in a service where every iota of such saving counts, has influenced many shipowners to adopt the steel.