Lives of the Engineers / The Locomotive. George and Robert Stephenson

by Samuel Smiles

He was encouraged to persevere in the completion of his safety-lamp by the occurrence of several fatal accidents about this time in the Killingworth pit. On the 9th November a boy was killed by a blast in the A pit, at the very place where Stephenson had made the experiments

with his first lamp; and, when told of the accident, he observed that if the boy had been provided with his lamp, his life would have been saved. On the 20th November he went over to Newcastle to order his third lamp from a plumber in that town. The plumber referred him to his clerk, whom Stephenson invited to join him at a neighbouring public-house, where they might quietly talk over the matter, and finally settle the plan of the new lamp. They adjourned to the “Newcastle Arms,” near the present High Level Bridge, where they had some ale, and a design of the lamp was drawn in pencil upon a half-sheet of foolscap, with a rough specification subjoined. The sketch, when shown to us by Robert Stephenson some years since, still bore the marks of the ale. It was a very rude design, but sufficient to work from. It was immediately placed in the hands of the workmen, finished in the course of a few days, and experimentally tested in the Killingworth pit like the previous lamps, on the 30th November. At that time neither Stephenson nor Wood had heard of Sir Humphry Davy’s experiments nor of the lamp which that gentleman proposed to construct.

An angry controversy afterwards took place as to the respective merits of George Stephenson and Sir Humphry Davy in respect of the invention of the safety-lamp. A committee was formed on both sides, and the facts were stated in various ways. It is perfectly clear, however, that Stephenson had ascertained the fact that flame will not pass through tubes of a certain diameter—the principle on which the safety-lamp is constructed—before Sir Humphry Davy had formed any definite idea on the subject, or invented the model lamp afterwards exhibited by him before the Royal Society. Stephenson had actually constructed a lamp on such a principle, and proved its safety, before Sir Humphry had communicated his views on the subject to any person; and by the time that the first public intimation had been given of his discovery, Stephenson’s second lamp had been constructed and tested in like manner in the

Killingworth pit. The first was tried on the 21st October, 1815; the second was tried on the 4th November; but it was not until the 9th November that Sir Humphry Davy presented his first lamp to the public. And by the 30th of the same month, as we have seen, Stephenson had constructed and tested his third safety-lamp.

Stephenson’s theory of the “burnt air” and the “draught” was no doubt wrong; but his lamp was right, and that was the great fact which mainly concerned him. Torricelli did not know the rationale of his tube, nor Otto Gürike that of his air-pump; yet no one thinks of denying them the merit of their inventions on that account. The discoveries of Volta and Galvani were in like manner independent of theory; the greatest discoveries consisting in bringing to light certain grand facts, on which theories are afterwards framed. Our inventor had been pursuing the Baconian

method, though he did not think of that, but of inventing a safe lamp, which he knew could only be done through the process of repeated experiment. He experimented upon the fire-damp at the blowers in the mine, and also by means of the apparatus which was blown up in his cottage, as above described by himself. By experiment he distinctly ascertained that the explosion of fire-damp could not pass through small tubes; and he also did what had not before been done by any inventor—he constructed a lamp on this principle, and repeatedly proved its safety at the risk of his life. At the same time, there is no doubt that it was to Sir Humphry Davy that the merit belonged of having pointed out the true law on which the safety-lamp is constructed.

The subject of this important invention excited so much interest in the northern mining districts, and Stephenson’s numerous friends considered his lamp so completely successful—having stood the test of repeated experiments—that they urged him to bring his invention before the Philosophical and Literary Society of Newcastle, of whose apparatus he had availed himself in the course of his experiments on fire-damp. After much persuasion he consented, and a meeting was appointed for the purpose of receiving his explanations, on the evening of the 5th December, 1815. Stephenson was at that time so diffident in manner and unpractised in speech, that he took with him his friend Nicholas Wood, to act as his interpreter and expositor on the occasion. From eighty to a hundred of the most intelligent members of the society were present at the meeting, when Mr. Wood stood forward to expound the principles on which the lamp had been formed, and to describe the details of its construction. Several questions were put, to which Mr. Wood proceeded to give replies to the best of his knowledge. But Stephenson, who up to that time had stood behind Wood, screened from notice, observing that the explanations given were not quite correct, could no longer control his reserve, and, standing forward, he proceeded in his strong Northumbrian dialect, to describe the lamp, down to its

minutest details. He then produced several bladders full of carburetted hydrogen, which he had collected from the blowers in the Killingworth mine, and proved the safety of his lamp by numerous experiments with the gas, repeated in various ways; his earnest and impressive manner exciting in the minds of his auditors the liveliest interest both in the inventor and his invention.

Shortly after, Sir H. Davy’s model lamp was received and exhibited to the coal-miners at Newcastle, on which occasion the observation was made by several gentlemen, “Why, it is the same as Stephenson’s!”