FRANCIS PETTIT SMITH: PRACTICAL INTRODUCER OF THE SCREWPROPELLER.
"The spirit of Paley's maxim that 'he alone discovers who proves,' is applicable to the history of inventions and discoveries; for certainly he alone invents to any good purpose, who satisfies the world that the means he may have devised have been found competent to the end proposed."--Dr. Samuel Brown.
"Too often the real worker and discoverer remains unknown, and an invention, beautiful but useless in one age or country, can be applied only in a remote generation, or in a distant land.
Mankind hangs together from generation to generation; easy labour is but inherited skill; great discoveries and inventions are worked up to by the efforts of myriads ere the goal is reached."--H. M. Hyndman.
Though a long period elapsed between the times of Phineas Pett and "Screw" Smith, comparatively little improvement had been effected in the art of shipbuilding. The Sovereign of the Seas had not been excelled by any ship of war built down to the end of last century.At a comparatively recent date, ships continued to be built of timber and plank, and impelled by sails and oars, as they had been for thousands of years before.
But this century has witnessed many marvellous changes. A new material of construction has been introduced into shipbuilding, with entirely new methods of propulsion. Old things have been displaced by new; and the magnitude of the results has been extraordinary. The most important changes have been in the use of iron and steel instead of wood, and in the employment of the steam-engine in impelling ships by the paddle or the screw.
So long as timber was used for the construction of ships, the number of vessels built annually, especially in so small an island as Britain, must necessarily have continued very limited.
Indeed, so little had the cultivation of oak in Great Britain been attended to, that all the royal forests could not have supplied sufficient timber to build one line-of-battle ship annually; while for the mercantile marine, the world had to be ransacked for wood, often of a very inferior quality.
Take, for instance, the seventy-eight gun ship, the Hindostan, launched a few years ago. It would have required 4200 loads of timber to build a ship of that description, and the growth of the timber would have occupied seventy acres of ground during eighty years.It would have needed something like 800,000 acres of land on which to grow the timber for the ships annually built in this country for commercial purposes. And timber ships are by no means lasting. The average durability of ships of war employed in active service, has been calculated to be about thirteen years, even when built of British oak.
Indeed, years ago, the building of shipping in this country was much hindered by the want of materials.
The trade was being rapidly transferred to Canada and the United States. Some years since, an American captain said to an Englishman, Captain Hall, when in China, "You will soon have to come to our country for your ships: your little island cannot grow wood enough for a large marine." "Oh!" said the Englishman, "we can build ships of iron!" "Iron?" replied the American in surprise, "why, iron sinks; only wood can float!" "Well! you will find I am right." The prophecy was correct. The Englishman in question has now a fleet of splendid iron steamers at sea.
The use of iron in shipbuilding had small beginnings, like everything else. The established prejudice--that iron must necessarily sink in water--long continued to prevail against its employment. The first iron vessel was built and launched about a hundred years since by John Wilkinson, of Bradley Forge, in Staffordshire. In a letter of his, dated the 14th July, 1787, the original of which we have seen, he writes: "Yesterday week my iron boat was launched. It answers all my expectations, and has convinced the unbelievers, who were 999 in 1000. It will be only a nine days' wonder, and afterwards a Columbus's egg." It was, however, more than a nine days' wonder; for wood long continued to be thought the only material capable of floating.
Although Wilkinson's iron vessels continued to ply upon the Severn, more than twenty years elapsed before another shipbuilder ventured to follow his example. But in 1810, Onions and Son, of Brosely, built several iron vessels, also for use upon the Severn. Then, in 1815, Mr. Jervons, of Liverpool, built a small iron boat for use on the Mersey. Six years later, in 1821, Mr.
Aaron Manby designed an iron steam vessel, which was built at the Horsley Company's Works, in Staffordshire. She sailed from London to Havre a few years later, under the command of Captain (afterwards Sir Charles) Napier, RN. She was freighted with a cargo of linseed and iron castings, and went up the Seine to Paris. It was some time, however, before iron came into general use. Ten years later, in 1832, Maudslay and Field built four iron vessels for the East India Company. In the course of about twenty years, the use of iron became general, not only for ships of war, but for merchant ships plying to all parts of the world.
When ships began to be built of iron, it was found that they could be increased without limit, so long as coal, iron, machinery, and strong men full of skill and industry, were procurable. The trade in shipbuilding returned to Britain, where iron ships are now made and exported in large numbers; the mercantile marine of this country exceeding in amount and tonnage that of all the other countries of the world put together. The "wooden walls"of England exist no more, for iron has superseded wood. Instead of constructing vessels from the forest, we are now digging new navies out of the bowels of the earth, and our "walls," instead of wood, are now of iron and steel.
