The Life of George Stephenson and of his Son Robert Stephenson / Comprising Also a History of the Invention and Introduction of the Railway Locomotive

by Samuel Smiles

Trevithick, nevertheless, seems to have been on the highway to fortune, for, at the beginning of 1806, he had received orders for nine engines in one month, all for Cornwall; and he expected orders for four others. He had also in view the construction of a railway; but nothing came of this project. More hopeful still, as regarded immediate returns, was the Cornish engine business, which presented a very wide field. Now that the trade had been thrown open by the expiry of Boulton and Watt's patent, competition had sprung up, and many new makers and inventors of engines were ready to supply the demand.

Among the most prominent of these were Trevithick and Woolf. Trevithick was the most original and speculative, Woolf the most plodding and practical, and the most successful. Trevithick's ingenuity exhibited itself in his schemes for working Boulton and Watt's pumping-engine by high-pressure steam, by means of his cylindrical wrought-iron boiler. He proposed to expand the steam down to low pressure previous to condensation, thereby anticipating by many years the Cornish engine now in use. The suggestion was not, however, then acted on, and he fell back on his original design of a simple non-condensing high-pressure engine. One of these was erected at Dalcoath mine to draw the ores there. It was called "the puffer" by the mining people, from its puffing the steam direct into the air; but its performances did not compare favorably with those of the ordinary condensing engines of Boulton and Watt, and the engine did not come into general use.

Trevithick was not satisfied to carry on a prosperous engine business in Cornwall. Camborne was too small for him, and the Cornish mining districts presented too limited a field for his ambitious spirit. So he came to London, the Patent-office drawing him as the loadstone does the needle. In 1808 he took out two patents, one for "certain machinery for towing, driving, or forcing and discharging ships and other vessels of their cargoes," and the other for "a new method of stowing cargoes of ships." In 1809 he took out another patent for constructing docks, ships, etc., and propelling vessels.

In these patents, Trevithick was associated with one Robert Dickinson, of Great Queen Street, but his name stands first in the specification, wherein he describes himself as "of Rotherhithe, in the county of Surrey, engineer." By the first of these patents he proposed to tow vessels by means of a rowing wheel shaped like an undershot water-wheel furnished with floats placed vertically in a box, and worked by a steam-engine, which he also proposed to employ in the loading and unloading of the vessel, but it is not known that the plan was ever introduced into practical use. The patent of 1809 included a floating dock or caisson made of wrought-iron plates, in which a ship might be docked while afloat, and, after the water had been pumped out of the caisson, repaired without moving her stores, masts, or furniture. This invention has since been carried out in practice by the Messrs. Rennie in the floating iron dock which they have recently constructed for the Spanish government. Another invention included in the specification was the construction of merchant and war ships of wrought-iron plates strongly riveted together, with their decks supported by wrought-iron beams, and the masts, bowsprits, and booms also of tubular wrought iron, thereby anticipating by many years the form and structure of vessels now in common use.

While Trevithick lived at Rotherhithe, he entered upon a remarkable enterprise—no less than the construction of a tunnel under the Thames—a work which was carried out with so much difficulty by Sir Isambard Brunel some twenty years later. Several schemes had been proposed at different times for connecting the two banks of the river by an underground communication. As early as 1798, Ralph Dodd suggested a tunnel under the Thames between Gravesend and Tilbury, and in 1802 Mr. Vazie projected a tunnel from Rotherhithe to Limehouse. A company was formed to carry out the latter scheme, and a shaft was sunk, at considerable expense, to a depth of 76 feet below high water. The works were from time to time suspended, and it was not until the year 1807, when Trevithick was appointed engineer of the work, that arrangements were made for proceeding with the driftway under the bed of the Thames. After about five months' working, the drift was driven for a length of 953 feet, when the roof gave way and the water burst in. The opening was, however, plugged by clay in bags thrown into the river, and the work proceeded until 1028 feet had been accomplished. Then the water burst in again, and the process of plugging and pumping the water out of the drift was repeated. After seventy more feet had been added to the excavation, there was another irruption, which completely flooded the driftway, and the water rose nearly to the top of the shaft. This difficulty was, however, again overcome, and with great danger twenty more feet were accomplished; but the bursts of water became so frequent and unmanageable that at length the face of the drift was timbered up and the work abandoned. Trevithick, who had been promised a reward of £1000 if the tunnel succeeded, thus lost both his labor and his reward. The only remuneration he received from the Company was a hundred guineas, which were paid to him according to agreement, provided he carried the excavation to the extent of 1000 yards, which he did.

Trevithick returned to Camborne in 1809, where we find him busily occupied with new projects, and introducing his new engine worked by water-power, the first of which was put up at the Druid mine, as well as in perfecting his high-pressure engine and its working by expansion. One of the first of such engines was erected at the Huel Prosper mine, of which he was engineer; and this, as well as others subsequently constructed on the same principle, proved quite successful.

In 1815 Trevithick took out a farther patent, embodying several important applications of steam-power. One of these consisted in "causing steam of a high pressure to spout out against the atmosphere, and by its recoiling force to produce motion in a direction contrary to the issuing steam, similar to the motion produced in a rocket, or to the recoil of a gun." This was, however, but a revival of the ancient Œolipile described by Hero, and known as "Hero's engine."

In another part of his specification Trevithick described the screw-propeller as "a screw or a number of leaves placed obliquely round an axis similar to the vanes of a smoke-jack, which shall be made to revolve with great speed in a line with the required motion of the ship, or parallel to the same line of motion." In a second part of the specification, he described a plunger or pole-engine in which the steam worked at high-pressure. The first engine of this kind was erected by Trevithick at Herland in 1815, but the result was not equal to his expectations, though the principle was afterward successfully applied by Mr. William Sims, who purchased the patent-right.

In this specification Trevithick also described a tubular boiler of a new construction for the purpose of more rapidly producing high-pressure steam, the heating surface being extended by constructing the boiler of a number of small perpendicular tubes, closed at the bottom, but all opening at the top into a common reservoir, from whence they received their water, and into which the steam of all the tubes was united.

While Trevithick was engaged in these ingenious projects, an event occurred which, though it promised to issue in the most splendid results, proved the greatest misfortune of his life. We refer to his adventures in connection with the gold mines of Peru. Many of the richest of them had been drowned out, the pumping machinery of the country being incapable of clearing them of water. The districts in which they were situated were almost inaccessible to ordinary traffic, all transport being conducted on the backs of men or of mules. The parts of an ordinary condensing engine were too ponderous to be carried up these mountain heights, and it was evident that, unless some lighter sort of engine could be employed, the mines in question must be abandoned.