David Pollock

“ SAFETY AND COMFORT OF MODERN STEAMSHIPS. Every advance—whether it be in dimensions or power of steamships, or whether it consist of modifications in their structure or appointment—toward that ideal period when sea-voyaging will have attained its maximum of comfort and its minimum of risk, is deserving of record. The qualities of safety and comfort, even more than increase of speed and the consequent shortening of sea passages, are first essentials in the realisation of this great end. ”

“ To meet the exigencies of the progressive movement, both practical skill, scientific knowledge, and commercial enterprise have been needed on the part of our shipbuilders. These have not been by any means wanting, as abundantly evidenced by the foregoing record of what has been achieved. With a continuance of that readiness displayed by shipbuilders and naval architects to modify, and even revolutionize if need be, types and methods which the times have outgrown, the lead in merchant shipbuilding will long be ours. ”

“ The insurance companies, on whom the burden (monetary at least) of loss at sea ultimately falls, see it their interest to know that those registration societies, on whom they rely for guarantee as to a vessel’s structural and general efficiency, are themselves efficient and trustworthy authorities. These societies, known as Lloyd’s, Liverpool Underwriters, and Bureau Veritas, Registries, in spite of the dread as to business rivalry affecting injuriously their standards of classification, have still a high criterion, and enjoy the confidence of insurance societies and shipowners alike. ”

“ The development by a vessel’s engines of the power requisite to drive her at a certain speed is always very considerably more than the power required simply to overcome her total resistance at that speed. ”

“ Commercially, it is of the utmost importance that increase of speed and power should be achieved, with the least possible weight of machinery, water, and fuel to be carried; with the least possible expenditure of fuel; with safety and efficiency in working; with low wear and tear, and cheapness of maintenance.
The efficiency of the ship and machinery in fulfilling the various and often conflicting conditions of economical service is a matter with which the naval architect and the marine engineer have jointly to deal. ”

“ Instead of the flickering and somewhat clumsy oil lamps, the electric system presents, encased in neat, tiny, glass globes, a steady, mellow white light, the adaptability of which to any conceivable position or design is one of its most beautiful properties. ”

“ In whatever way it is accomplished, I look to the use of machine riveting as one very great step in advance in the future improvement of the riveted joints of iron ships; and if the weight of iron vessels is to be reduced in any important degree, or if the dimensions and proportions of large merchant steamers are to increase in the future as they have done in the past, I feel sure that one of the first steps must be the reconsideration of our butt fastenings. ”

“ In cargo-carrying vessels, for example, an economy in the consumption of fuel may often be the dominant and regulating quality. An economy of one-fourth of a pound per horse-power per hour gives, on a large transatlantic steamer, a saving of about 100 tons of coal for a single voyage. To this saving of cost is to be added the gain in wages and sustenance of the labour required to handle that coal, and the gain by 100 tons of freight carried in place of the coal. Again, it is estimated that every ton of dead-weight capacity is worth on an average £10 per annum as earning freight. ”

“ In every well-appointed passenger ship for ocean service, the electric light has already supplanted the former method of lighting the saloons, state-rooms, and machinery spaces, by means of oil lamps, which has so often proved a fruitful source of annoyance to passengers and crew, if not, indeed, of positive danger to the vessel herself.
The advantages of the change are such as constitute the electric light an invaluable acquisition on board every modern passenger steamship. The light gives off very little heat, there is no smell, no products of combustion to produce headaches and sickness. ”

“ Questions of resistance to the progress of the ship were therefore subordinated to sail-carrying power and handiness in sailing ships; whereas in steamers designed for a certain speed the question of resistance occupies a primary place, seeing that the engine power must be proportioned to the resistance. Consequently, while keeping in view stability, handiness, and structural strength, the designer of a steamer has a more difficult task than the designer of a sailing ship, and the difficulty can only be met if faced intelligently by scientific analysis. ”

“ Shipowners are too ready to shut their minds against everything which seeks the acme of comfort and safety by other means than those which guarantee economical success, or those which consist in increasing the size and power, and enhancing the accommodation of conventional types of vessels. These novelties and innovations, on the other hand, represent more of the intrepidity essential to genuine advancement than is forthcoming in a thousand merchant ships of the conventional type. ”

“ In the whole world there is no place whatever that can in any degree compare with the Clyde for either extent or quality of steamship building; and at this moment an indisputable verification can be adduced, for between American and European ports there are at the present time something like a score of steam navigation companies, doing an immense passenger and carrying trade, with vessels of great power and magnificence, and notwithstanding the variety of trade nationalities, at least two-thirds of the vessels employed were built and equipped on the Clyde ”

“ 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 ”

“ With regard to such fundamental properties of vessels as displacement, weight, and carrying capability, nothing new has for a long period been added to the fund of scientific knowledge. One of the conditions now most commonly laid down by the owners of a proposed ship is that which provides for a certain carrying capability on a given draught of water and at a certain speed, the principal dimensions of the vessel also being stipulated. ”

“ The question of stability, which has next to be considered, is one of great difficulty and intricacy, and it was not till the middle of last century that some of the principles upon which it depends began to be understood. Bouguer showed in 1746 that the position of the “metacentre” limits the height to which the centre of gravity of a floating body may be raised without making it unstable, and that the righting moments at small angles of inclination from a position of stable equilibrium are proportional to the height of the metacentre above the centre of gravity. ”

“ Reverting to the subject of the proportion of material requiring to be heated before manipulation, it is noteworthy that the employment of mild steel is a source of economy in this connection as well as in the many others already noticed. The superior homogeneity and great ductility of the material favours cold-bending when such an operation would be fatal to iron. Not only does an economy in labour result, but incidentally there is a further advantage. ”

“ Not so long ago endeavours were seldom made to extract lessons of general value from particular occurrences, there being a disposition prevalent to accept facts without accounting for them—“to rejoice in a success and regard a failure as irreparable”—the outcome, it may at once be said, of indifference, false ideas of economy, and of a limited conception of the part scientific methods should play in successful shipbuilding. ”

“ The whole tendency of our time is towards the aggregation of effort: the massing of [3] capital and labour. A vessel of five thousand tons can be built cheaper than five vessels of one thousand tons. In the manning and working of ships there is a still more striking economy, e.g., one captain instead of five, and so on throughout the staff of officers, engineers, stewards, and crew. Not only so, but long ships can be propelled at greater speeds than short ones, the whole conditions of construction, engines, and propellers being considered. ”

“ Hydraulic presses have been used for this purpose for some years, a certain proportion of the work done being the manipulation of plates while cold. With steel as the material to be operated upon, these machines are being more and more utilised in this direction, and their presence in the shipyard, as in boiler works, is sure to become more and more prevalent. The operations of the shipyard, in short, have been gaining in exactitude every year, and have borrowed both in the matters of methods and of appliances from the marine boiler works, where machine tools are more conspicuously a feature. ”

“ The general question of seaworthiness, affected as it is by matters almost beyond the province of the marine architect, is in great measure the care of others concerned. The underwriting or insurance societies looking to their own interests, the Board of Trade on behalf of the lieges, and shipowners on their own and their customers’ and servants’ account, are parties on whom responsibility devolves in this connection. The question whether they are duly, and at all times alive to such responsibility, is one very difficult to answer, and cannot be fully dealt with here. ”

“ Coincident with the changes made in the dimensions and structure of vessels, there are numerous features of enhanced comfort for passengers and crew which are deserving of notice. Notably is this manifest in the arrangement of saloons and state-rooms—their appointment, lighting, and ventilation. The character of steamships for the great ocean [67] highways in this respect is above and beyond anything which Board of Trade enactments seek to secure. The amount of spirited competition itself on those services, acts as an efficient promoter of excellence in design and equipment. ”

“ Progress in the pure science of naval architecture, as distinguished from the practical application of scientific rules and principles to shipbuilding, is a great and complex subject, and one which it would be impossible to do full justice to here. ”

“ Shipowners themselves, notwithstanding some examples to the contrary, are, and have always been, anxious and painstaking seekers after thoroughness; not merely mercenary grubs, sacrificing considerations of safety to features promising exemption from tonnage or other registration dues, and perhaps the extinction of a rival. Some of the best British vessels, notably those of the Cunard Line, are unclassed at the registries, but have been built under private survey. ”

“ American shipbuilders thus secured from the encroaches of foreign competition, have enjoyed their own pace, but at too great a sacrifice. Preferring to take the material most at hand, the manipulation of which they well understood, they have allowed their wood age to be dove-tailed thirty years into our iron one, with the other result that America now occupies as unimportant a place in the traffic of the sea, as the above quotation indicates. ”

“ The crowning case of all is that of the building firms themselves—many shipbuilders unquestionably being conscientious and thorough to a degree which simply mocks this great array of supervision.
In the outfit of vessels correspondingly close attention is paid to those features, fixed or portable, which contribute to the safety of the ship and the welfare of passengers. The universal adoption of steam winches for working cargo enables the pumps communicating with the holds to be wrought by steam, through levers attached to the barrel ends of the winches. ”

“ If, for example, a ship is to be built of virtually similar dimensions and form to one for which such information is available, but of less speed, the task is simply one of measurement from the curves, with some allowance for probable differences in the constant friction of the engines. If the speed is to be greater than that of the exemplar ship, but still within the limits when wave-making resistance assumes relative importance, the case is also one of simple reading from the curves, with slight corrections. ”

“ PROGRESS IN METHODS OF SHIPYARD WORK. Since the early days of iron shipbuilding, when hand labour entered largely into almost all the operations of the shipyard, the field of its application has been gradually narrowed by the employment of machinery. The past few years have been uncommonly fruitful of changes in this direction, and many things point to the likelihood of manual work being still more largely superseded by machine power in the immediate future. ”

“ 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. ”