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While thus occupied in his country house at Tapton, many persons continued to seek Mr. Stephenson's advice on subjects connected with mechanical engineering. Inventors sent their plans to him, and his approval was regarded as a passport to success. He was always ready to consider the plans thus submitted. Sometimes it was a paddle-boat for canals. or a new brake for railway trains, or a steam-gauge, or a patent axle. If his reply proved favourable, the inventor occasionally seized the opportunity of circulating or advertising it, often without asking his permission.
One gentleman requested his opinion respecting his "antifriction wheeled carriages," to which a very civil letter was sent in reply, containing some useful hints, and offering to subscribe towards having a carriage properly constructed after a carefully prepared model, but cautioning the inventor against being over-sanguine. "If I can be the means of helping you," said he, "I shall be glad to do so; but I should not be justified in leading you or any other person to spend money without any chance of getting it back again." This letter was immediately published in the railway papers by the happy inventor, with a quantity of doggrel appended: but if the proposed wheel ran no smoother than the rhymes it could not have been worth much.*
* Take the following specimen: —
"I saw your son Robert, oh fie! oh fie! He looked upon me with disdain;
Chap, xxxv.] BEALE'S KOTATOBY ENGINE. 483
Another inventor induced a mutual friend to write requesting his opinion respecting an improved steam-boat for the working of canals. He wrote in reply, commending the plan of the boat, but at the same time expressing his belief that " no boat can be made now to work against the locomotive." When Beale's Rotatory Engine came out, although entertaining a strong opinion against it, he nevertheless subscribed a sum of money for the purpose of having it fairly tried. A boat was fitted up with the engine, and the trial came off at Yarmouth. After describing the experiment at a meeting of the Mechanical Engineers, he said, " When the engine was put to work, we could not get the boat to move forward, and the experiment failed. We managed, indeed, to get the boat to sea, but it cost me and the party 40/. to bring her back again."
While Mr. Stephenson was in the full tide of railway business in London, these frequent applications of inventors to submit their plans for his consideration had not always been so favourably received. They broke in upon him at a time when every moment was precious, pre-engaged by railway companies with large interests at stake. Absorbed by work, and his mind full of the business in hand, it was scarcely to be expected that he should listen with patience to plans fifty times before proposed and rejected,— to crude and wild theories believed in only by their projectors. But when he
His father could see, with half an eye,
• "Ho would n't allow me to leave him my models.
Or a drawing, nor yet read my rhyme;
The last two lines state a fact beyond dispute. The number of inventions in connection with railways thrust upon the Messrs. Stephenson for their opinion during the railway mania, was almost beyond computation.
Chap, xxxv.] THBEE-CYLINDER LOCOMOTIVE. 485
of the pressure of steam; it is quite from under the control of the engineer, or any other person, so that its indications may be relied upon; and the construction is so simple, that it is scarcely possible for it to get out of order, I might give a full explanation of the machine, but I think it best to leave that to the inventor himself. The numerous and appalling accidents which have occurred from the bursting of steam-boat boilers have induced me to give you these observations, which I think desirable to be laid before the public. I may state that I have no pecuniary interest in the scheme; but being the first person to whom it has been shown, and the first to make use of it, I feel it a duty I owe to the inventor, as well as the public, to make it as universally known as possible. The indicator is put up at Tapton colliery, near Chesterfield, and may be seen any day, by any respectable person."
Mr. Stephenson also occupied some of his spare time, while at Tapton, in devising improvements in locomotive engines and railway carriages, still aiming at perfecting the great system which he had originated. Thus, in 1846, he brought out his design of a three-cylinder locomotive,— the two outside cylinders acting together in the same plane, the third cylinder, with a crank in the middle of the axle, acting at right angles to the plane and crank pins of the two other cylinders. The middle cylinder was double the diameter of the others; and its compensating action neutralised the tendency to oscillate, which was a defect in the long-boiler outside-cylinder engines as originally constructed. Although this new engine was very ingenious, and acted with great power, it has not come into general use, in consequence of the somewhat greater expense of its construction and working. The oscillation, also, of the outside-cylinder engines, which this invention was designed to correct, has since been obviated by an improvement in their design and structure. A three-cylinder engine was, however, constructed by way of experiment for the North Eastern Railway, on which line it still continues in efficient work."
Shortly after, Mr. Stephenson invented a new self-acting brake, after a plan which had occupied his attention for many years, and which had been partially adopted on the Liverpool and Manchester Railway during the time that he was its acting engineer. He now communicated a paper on the subject, accompanied by a beautiful model, to the Institute of Mechanical Engineers at Birmingham, of which he was president. The great recommendation of the plan wa9 its simplicity and cheapness. "Any effectual plan," he said, "for increasing the safety of railway travelling is, in my mind, of such vital importance, that I prefer laying my scheme open to the world to taking out a patent for it; and it will be a source of great pleasure to me to know that it has been the means of saving even one human life from destruction, or that it has prevented one serious concussion." *
In 1847, the year before his death, Mr. Stephenson was invited to join a distinguished party at Sir Robert Peel's mansion at Drayton Manor, and to assist in the ceremony of formally opening the Trent Valley Railway, which had been originally designed and laid out by him many years before. The first sod of the railway was cut by the Prime Minister himself, in November, 1845, during the time when Mr. Stephenson was abroad on the business of the Spanish rail
* Sec the "Practical Mechanic's Journal," voL i. p. 53., for a description of the Self-acting Brake, since revived by M. Guerin, with the addition of» centrifugal apparatus. Mr. Stephenson's original idea, of employing ll* momentum or surplus velocity of the train for the purpose of braking tb« wheels of the carriages, and thereby stopping the train, has been ingeniooslr worked out by M. Guerin, who admits that his invention is but the compkment of the Self-acting Brake above referred to.