still greater rarity is the beam engine model made by Watt himself. This model works the steam valve, by what is termed the tippit motion. An additional interest attaches to it over and above the fact that it is one of the first ideas of the great motive power of the present day, inasmuch as Watt always kept it under his own observation in his drawing-room. It is but rudely finished, but the very fact that its great inventor’s eye dwelt upon it with pride and triumph invests it with a poetry all its own. Another beam engine, once belonging to Watt, with parallel motion attached to the piston-rod, is a better example of mechanical skill. We have not far to look for the first germ of steam navigation. That huge model which appears to be a combination of two funnels and a number of chains working over wheels is the parent marine engine. As early as the year 1787, Patrick Miller, of Dalswinton, Scotland, engaged himself in making experiments with double and treble boats, which he propelled by means of wheels placed between them worked by manual labour; in the following year he induced one Symington, an engineer, at Wenlock Head, to apply to it a marine steam engine he had invented. This engine propelled the boat along Dalswinton Lake at the rate of five miles an hour. This was undoubtedly the first attempt ever made to use steam as the motive power in a vessel; although it was not the first practical steam-boat. The engine which belongs to the earliest history of that invention, is what is called an atmospheric engine, that is, the piston is raised by the action of steam, and then it is forced down by atmospheric pressure. The history of this curious parent of steam navigation is worth noting. After the trial in the boat, the engine was removed to Mr. Miller’s library, where it remained until his death in 1815; in 1828, it was sent by his son, packed in a deal case, to Messrs. Coutts & Co., in the Strand, where it remained until 1837, and finally it found its way to a plumber’s in Edinburgh, who flung it aside with the purpose of melting it. However, the model was rescued from destruction, and in 1855 was restored to its former working condition by Messrs. Penn & Son in 1857.
It is usually supposed that the boat made by Fulton, in America, was the first practical steamboat; but that honour must be transferred to Symington, who, in 1801, perceiving that his old engine was too complicated to work practically, completed a new one with the later improvements by Watt and others, and placed it on board the Charlotte Dundas, which was, in truth, the first practical steamboat. The paddle was still a problem which puzzled mechanicians. Its best form, so as to offer the least resistance on entering and leaving the water, engaged the skill of hundreds of thoughtful men, many of whose models are to be seen in the museum. But other minds were intent upon superseding the wheel altogether, and, at last, Captain Smith’s screw did so. We can all remember the fierce disputes there were among nautical men with respect to the relative powers of paddle versus screw—a dispute which was finally settled by the tournament which took place between her Majesty’s steamer Rattler, screw steamer, and the Electro, paddle-boat, both of equal size and power. They towed stern to stern, and the propeller dragged the paddle after her at the rate of two and a-half miles an hour. This victory seems to have put an end to all attempts to improve the paddle, and now human ingenuity seems concentrated upon the screw. The number of patents taken out for different forms of the propeller is something extraordinary, and the models in the museum are in themselves a curiosity. Every degree of pitch that can be got out of a spiral, would seem to be exhausted, and the favourite design of screw now appears to be modelled in the shape of a blade-bone. The screw of the Rattler, for instance, ten feet in diameter, looks like the remains of the scapulæ of some gigantic Ichthyosaurus. Thus we go on improving upon each other’s efforts, every one adding some trifling improvement until perfection is attained.
Five minutes’ walk through this museum is sufficient to satisfy me of the profundity of the remark that “it is society that invents.” Let us take the subject of steam as a motive power, and let us see how long the idea has been before the world. Here, on the walls, we find a coloured drawing of Hero’s steam-engine invented 130 years before Christ! We can scarcely conceive that whilst Pan was still young, and whilst great was Diana of the Ephesians, the thin white vapour which now moves the world was even then dandled as a second infant Hercules. Hero’s idea of the application of the elastic force of the youthful giant was confined to simply projecting it against the resisting medium of the air—a hollow spindle connecting with two arms turned in opposite directions being filled with steam, the two jets acting on the air, gave the simple machine a revolving action. What centuries of thought lie between this and the great engine of the Leviathan steamer, a model of which is to be found in this room.
In these centuries we find the names of Solomon De Caus, Giovanni Branca, Torricelli, the Marquis of Worcester, Denis Papin, Thomas Savery, Thomas Newcomen, and Watt, to say nothing of the host of inventors who have added improvements in the present century. All of these studious men have nursed the mighty infant through the ages, until its limbs present their present gigantic proportions; and yet we say, familiarly enough, that steam is still in its infancy, and, without doubt, the New Zealander, could he exhume the museums of science of his day, will be able to read a list of improvers of steam as numerous as those we have already had.
Another great element of our present civilisation is beginning to make signs of its existence in this museum. We allude to the electric telegraph. Bakewell’s Copying Machine is one of the most interesting of this class, as it brings before the public eye the means that can be employed to write with a pen thousands of miles in length. If the Atlantic cable were in working order, for instance, a man through its instrumentality could sit down to write a letter in London, and feel certain that a fac-simile of his handwriting was at the same moment coming out of the telegraph office at New York. The manner in which
