Another useful friend Davy also found in Mr. Gilbert, afterwards President of the Royal Society. Passing along one day, Mr. Gilbert observed a youth making strange contortions of face as he hung over the hutch gate of Borlase's house; and being told by a companion that he was "the son of Davy the carver," and very fond of making chemical experiments, he had a talk with the lad, and discovering his talents, was ever afterwards his staunch friend and patron.
Through his two friends, Mr. Gilbert and Mr. Watt, Davy formed the acquaintance of Dr. Beddoes, who was just setting up at Bristol, under the title of Pneumatic Institution, an establishment for investigating the medical properties of different gases; and who, appreciating his abilities, gave him the superintendence of the new institution.
Although only twenty years of age at this time, Davy was well abreast of the science of the day, and soon applied his vigorous and searching intellect to several successful investigations. His first scientific discovery was the detection of siliceous earth in the outer coating of reeds and grasses. A child was rubbing two pieces of bonnet cane together, and he noticed that a faint light was emitted; and on striking them sharply together, vivid sparks were produced just as if they had been flint and steel. The fact that when the outer skin was peeled off this property was destroyed, showed that it was confined to the skin, and on subjecting it to analysis silex was obtained, and still more in reeds and grasses.
As superintendent of Dr. Beddoe's institution, his attention was, of course, chiefly directed to the subject of gases, and with the enthusiasm of youth, he applied himself ardently to the investigation of their elements and effects, attempting several very dangerous experiments in breathing gases, and more than once nearly sacrificing his life. In the course of these experiments he found out the peculiar properties of nitrous oxide, or, as it has since been popularly called, "laughing gas," which impels any one who inhales it to go through some characteristic action,—a droll fellow to laugh, a dismal one to weep and sigh, a pugnacious man to fight and wrestle, or a musical one to sing.
At twenty-two years of age, such was the reputation he had acquired, that he got the appointment of lecturer at the Royal Institution, which was just then established, and found himself in a little while not only a man of mark in the scientific, but a "lion" in the fashionable world. Natural philosophy and chemistry had begun to attract a good deal of attention at that time; and Davy's enthusiasm, his clear and vivid explanations of the mysteries of science, and the poetry and imagination with which he invested the dry bones of scientific facts, caught the popular taste exactly. His lecture-room became a fashionable lounge, and was crowded with all sorts of distinguished people. The young lecturer became quite the rage, and was petted and feted as the lion of the day. It was only six years back that he was the druggist's boy in a little country town, alarming and annoying the household with his indefatigable experiments. He could hardly have imagined, as one of his day-dreams at the sea-side, that his fame would be acquired so quickly.
In spite of all the flatteries and attentions which were showered upon him, Davy stuck manfully to his profession; and if his reputation was somewhat artificial and exaggerated at the commencement, he amply earned and consolidated it by his valuable contributions to science during the rest of his career.
The name of Humphrey Davy will always be best known from its association with the ingenious safety lamp which he invented, and which well entitles him to rank as one of the benefactors of mankind. It was in the year 1815 that Davy first turned his attention to this subject. Of frequent occurrence from the very first commencement of coal-mining, the number of accidents from fire-damp had been sadly multiplied by the increase of mining operations consequent on the introduction of the steam engine. The dreadful character of some of the explosions which occurred about this time, the appalling number of lives lost, and the wide-spread desolation in some of the colliery districts which they had occasioned, weighed heavily on the minds of all connected with such matters. Not merely were the feelings of humanity wounded by the terrible and constant danger to which the intrepid miners were exposed, but it began to be gravely questioned whether the high rate of wage which the collier required to pay him not only for his labour, but for the risk he ran, would admit of the mines being profitably worked. It was felt that some strenuous effort must be made to preserve the miners from their awful foe. Davy was then in the plenitude of his reputation, and a committee of coal-owners besought him to investigate the subject, and if possible provide some preventative against explosions. Davy at once went to the north of England, visited a number of the principal pits, obtained specimens of fire-damp, analyzed them carefully, and having discovered the peculiarities of this element of destruction, after numerous experiments devised the safety-lamp as its antagonist.
The principles upon which this contrivance rests, are the modification of the explosive tendencies of fire-damp (the inflammable gas in mines) when mixed with carbonic acid and nitrogen; and the obstacle presented to the passage of an explosion, if it should occur, through a hole less than the seventh of an inch in diameter; and accordingly, while the small oil lamp in burning itself mixes the surrounding gas with carbonic acid and nitrogen, the cylinder of wire-gauze which surrounds it prevents the escape of any explosion. It is curious that George Stephenson, the celebrated engineer, about the same time, hit on much the same expedient.
To control a "power that in its tremendous effects seems to emulate the lightning and the earthquake," and to enclose it in a net of the most slender texture, was indeed a grand achievement; and when we consider the many thousand lives which it has been the means of saving from a sudden and cruel death, it must be acknowledged to be one of the noblest triumphs, not only of science, but of humanity, which the world has ever seen. Honours were showered upon Davy, from the miners and coal-owners, from scientific associations, from crowned heads; but all must agree with Playfair in thinking that "it is little that the highest praise, and that even the voice of national gratitude when most strongly expressed, can add to the happiness of one who is conscious of having done such a service to his fellow-men." Davy himself said he "valued it more than anything he ever did." When urged by his friends to take out a patent for the invention, he replied,—"No, I never thought of such a thing. My sole object was to serve the cause of humanity, and if I have succeeded, I am amply rewarded by the gratifying reflection of having done so."
The honours of knighthood and baronetage were successively conferred on Davy as a reward for his scientific labours; and the esteem of his professional brethren was shown in his election to the President-ship of the Royal Institution, in which, oddly enough, he was succeeded by his old friend Mr. Gilbert, who had first taken him by the hand, and whom he had got ahead of in the race of life.