The feasibility—in a scientific sense—of ships growing in proportions commensurate with the growth of commerce and traffic, has often been commented upon. The whole tendency of our time is towards the aggregation of effort: the massing of 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. Mr Robert Duncan, in his presidential address before the Society of Engineers and Shipbuilders in Glasgow in 1872, declared:—“Looking forward one generation, and measuring the future by the past, I think it is not problematical that we shall see steamers of eight hundred feet long the ferryboats of two oceans, with America for their central station, and Europe and Asia for their working termini.” Even since that was uttered, eleven years ago, we have approached, in solid practice, the limit thus laid down, by 150 feet at least. Three years previous to Mr Duncan’s address, vessels exceeding four hundred feet were not afloat, with the notable exception already referred to; now, there are few merchant fleets of any pretensions engaged in ocean traffic which do not include vessels over or approaching four hundred feet, and it is even no great boast that vessels close on six hundred feet are afloat and in active service. As better illustrating the growth in dimensions of merchant steamships, the Figs. on the following page may prove interesting. They show, all to the same scale, a number of representative steam vessels from the _Comet_ downwards. [Illustration: “COMET,” 1812. “ELIZABETH,” 1813. “INDUSTRY,” 1814. “CALEDONIA,” 1815. “ROB ROY,” 1818. “JAMES WATT,” 1822. “SIRIUS,” 1837. “GREAT BRITAIN,” 1843. “CITY OF GLASGOW,” 1850. “GREAT EASTERN,” 1857. “SCOTIA,” 1861. “COLUMBA,” 1878. “ARIZONA,” 1876. “SERVIA,” 1881. “CITY OF ROME,” 1881.] Along with the change or evolution in the sizes and types of merchant vessels, important modifications in their structural arrangement have of late years been effected, and it is to the constant progress being made in these matters—to the skill and intrepidity which are brought to bear on their execution, and to the readiness with which our shipowners recognise their importance and value—that the maintenance of our mercantile supremacy is largely owing. An American journal, writing a few years ago on this subject—perhaps with more of taunt for the conceit and self-sufficiency evinced by its own country than of adulation for the ability and enterprise displayed by ours—said:—