No small indignation was expressed by the friends of Sir Humphry Davy at Stephenson’s “presumption” in laying claim to the invention of the safety-lamp. In 1831 Dr. Paris, in his ‘Life of Sir Humphry Davy,’ thus wrote:—“It will hereafter be scarcely believed that an invention so eminently scientific, and which could never have been derived but from the sterling treasury of science, should have been claimed on behalf of an engine-wright of Killingworth, of the name of Stephenson—a person not even possessing a knowledge of the elements of chemistry.” But Stephenson was far above claiming for himself any invention not his own. He had already accomplished a far greater feat than the making of a safety-lamp—he had constructed a successful locomotive, which was to be seen in daily work on the Killingworth railway. By the improvements he had made in the engine, he might almost be said to have _invented_ it; but no one—not even the philosophers—detected the significance of that wonderful machine. What railways were to become, rested in a great measure with that “engine-wright of Killingworth, of the name of Stephenson,” though he was scarcely known as yet beyond the bounds of his own district. As to the value of the invention of the safety-lamp there could be no doubt; and the colliery owners of Durham and Northumberland, to testify their sense of its importance, determined to present a testimonial to its inventor. The friends of Sir H. Davy met in August, 1816, to take steps for raising a subscription for the purpose. The advertised object of the meeting was to present him with a reward for “the invention of _his_ safety-lamp.” To this no objection could be taken; for though the principle on which the safety-lamps of Stephenson and Davy were constructed was the same; and although Stephenson’s lamp was, unquestionably, the first successful lamp that had been constructed on such principle, and proved to be efficient,—yet Sir H. Davy did invent a safety-lamp, no doubt quite independent of all that Stephenson had done; and having directed his careful attention to the subject, and elucidated the true theory of explosion of carburetted hydrogen, he was entitled to all praise and reward for his labours. But when the meeting of coal-owners proposed to raise a subscription for the purpose of presenting Sir H. Davy with a reward for “his invention of _the_ safety-lamp,” the case was entirely altered; and Stephenson’s friends then proceeded to assert his claims to be regarded as its first inventor.