In the same year curious and important discoveries were made by M. Romme, professor of navigation at La Rochelle. In an endeavour to find the form of ship body which would give good stability in conjunction with small resistance, he ascertained the importance of the “run” or after part. Hitherto the form of bow had absorbed attention to the almost entire exclusion of the form of run, except in so far as it had been shaped to allow water to flow freely to the rudder. M. Romme called in aid methods which are now approved as scientific, but which were then conspicuously novel: he experimented by comparative trials between models in which all variable features except one had been carefully eliminated. He was rewarded by some new discoveries. By fixing the length and successively varying the curvature of different parts of his models he laid bare an important paradox. While at low speeds the resistance was least when a sharp end was in front and a blunt end in rear, at higher speeds the opposite obtained. This accounted for a great deal of the contradictions of previous investigators. M. Romme went further: the curves by which the bow of a ship was connected with her middle body, hitherto looked on as all-important, were shown to be relatively immaterial. He astonished the world of science by proving that, given certain conditions, the resistance upon an arc of a curve is the same as that upon the chord of this arc. His deductions were proved by commissions to be well founded. Experience confirmed that the form of the bow curve did not much influence the resistance experienced in passing through water; on the other hand the form of the run was shown to have a far greater effect than had hitherto been suspected.
In the year before M. Romme published the results of his experiments a treatise appeared, full of empirical rules and shrewd reasoning, by one of the greatest naval architects, Henry de Chapman, chief constructor of the Swedish navy, an Anglo-Swede who came of an old shipbuilding family of Deptford. Chapman was a most gifted shipbuilder. Though his formulæ were empirical, they were founded on careful observation and induction, and his name ranks with those of Phineas Pett and Anthony Deane in the history of naval architecture.
Nothing, so far, had come from English writers. “The only English treatise on shipbuilding that can lay any claim to a scientific character was published by Mungo Murray in 1754; and he, though his conduct was irreproachable, lived and died a working shipwright in Deptford dockyard.”[22] But indifference was at last giving place to interest. Inspired by the formation of the Society of Arts in 1753 (which Society was itself inspired by the recognition, on the part of the founder, of the value of prizes and rewards in improving our breed of racehorses) a London bookseller named Sewell succeeded in 1791 in forming a Society for the Improvement of Naval Architecture. “Impressed with the many grave complaints which reached him as to the inferiority of our warships as compared with those of France and Spain,” he gained the interest of Lord Barham and other influential men. A meeting was held at which it was decided, as something of a novelty, that the theory and art of shipbuilding were subjects of national importance; that a radical deficiency in knowledge of the same existed; and that the most effective remedy was a focussing of the wisdom of the country on this matter by the institution of the above Society.[23]
For a time the society flourished. A learned paper by Atwood before the Royal Society, on the stability of a rolling ship, proved that this country was not wholly destitute of mathematical talent. An interesting series of experiments was carried out for it by Colonel Beaufoy, a devoted student who had made his first experiments on water resistance before he was fifteen years old. It appears that his attention was first drawn to the subject by hearing an eminent mathematician state one evening that a cone drawn through water base foremost experienced less resistance than with its apex foremost; and it was said that sailors always took a mast in tow by the heel. The paradox excited young Beaufoy’s curiosity. Before bedtime, with the assistance of a neighbouring turner, he was making experiments in one of the coolers in his father’s brew-house, a large bunch of counting-house keys being put into requisition as a motive power. Though the society was dissolved in 1799 Beaufoy continued to pursue this subject with unabated zeal until his death. In one direction, especially, he did good work. Attracted by the frequency with which North Sea fishing vessels, fitted with wells for carrying the fish, foundered at sea, he showed experimentally the loss of stability involved in carrying open tanks of water. He also demonstrated to English builders by means of models that Bouguer’s diagram of metacentric stability was of great practical value, even for large angles of heel. “His experiments,” says Mr. Johns, “should take an important place in the history of stability of ships.”
§
We now revert to the beginning of the eighteenth century. In the desultory warfare which was carried on during the reign of Queen Anne events occurred to demonstrate the superiority in design of the French warship over its English opponent of the same nominal force. One in particular, an expedition under Count Forbin which was intended to cover a descent on the Scotch coast in favour of the Pretender, “showed, even in failure, that in material France held a lead on us.” Chased back to its ports from the latitude of Edinburgh by larger English forces, Forbin’s squadron proved a superiority over all our ships, both in speed and seaworthiness. In weather which disabled many of our vessels the French squadron arrived home with the loss of only three—and these all English built.
At about the same time the capture by us of a 60-gun ship, the Maure, of extraordinarily large dimensions for her rate, showed the direction in which French design differed from our own. The recapture, not long afterwards, of the Pembroke, which was now found to carry only fifty, instead of her original number of sixty-four guns, corroborated (says Charnock) the direction in which improvement was sought and found.
But for some time the lesson remained unlearnt. For a number of years the inferiority of our design was an accepted fact; “every action won by British valour was a stigma to British science.” Throughout the whole of this century we set no value on scientific principles as applied to naval architecture, and were content to remain copyists. Although before the advent of the Napoleonic wars we had thus endeavoured to reduce their balance of advantage, yet even so the French still maintained an absolute superiority in design. In the first half of the century this superiority was especially conspicuous; and, in conjunction with an inferiority of seamanship and workmanship which in the end more than neutralized all its advantages, it was the cause of the disreputable incongruities which Charnock has depicted in his well-known epigram: Very few ships captured by the enemy from the British have ever continued long the property of their possessors. If it has so happened, that one of them, being in company with others of French construction, has ever fallen in with any English squadron, that ship, almost without exception, has been among those captured, and most frequently the first which has fallen. On the other hand, the recapture of any ship from the British, which was originally French, is a circumstance extremely uncommon. Captured French ships were sought for as the best commands, which not infrequently were the means of recapturing captured English vessels.
Very seldom was our failure to overhaul the speedy Frenchman attributed to inferiority of design; nearly always to the fortuitous circumstance that we were foul-bottomed and the enemy clean; which may have been sometimes true, but which was evidently a partial and inaccurate explanation.
We have already made mention of the periodic “establishments” of dimensions to which ships built for the royal navy were made to conform. The first of these, after the rules laid down by the commissioners of James I, was decreed in 1655, when Blake was organizing a new standard navy. In 1677 dimensions were established for ships of 100, 90, and 70 guns, but were exceeded in the case of those ships which were actually built; and in ’91 a revised establishment for all classes, very similar to those which previously governed practice, appeared. In 1706 a new establishment was decreed, a compromise between the ideas of the Surveyor and the master shipwrights, in which the dimensions of each class were slightly increased. The dimensions still remained small compared with those of all foreign ships, however, and still “all superior faculties of sailing were attributed to the mere length of the vessel itself, without any but trivial regard to shape or form of bottom.” Assuming that the ships built under this establishment derived some slight advantage over earlier construction on account of their augmented tonnage, yet this was nullified when, in 1716, the force of their armament was raised. As the work of a committee presided over by Admiral Byng, a new establishment of guns was ordered, a change being made in calibres but not in numbers:—