He was appointed Assistant Lecturer in Chemistry to the Royal Institution in 1801. He had now entered on manhood, and was launched on the great world of London, having all the ability to carry himself through. He may have been handicapped with slight flaws of manner. If he appeared over-confident, it probably was that in reality he was shy and timid, and attempted to cover these little awkwardnesses. His friends grieved in secret over the noticeable change, fearing lest with simplicity of manner he might throw over simplicity of character. But no man is, after all, perfect, and in spite of this, Davy was rapidly mounting the ladder of success. The young chemist soon discovered that his lectures drew crowds, even created a great and extraordinary sensation. In imagination we can picture the lecture-room, the crowded audience--all sorts and conditions, from lovers of science, ladies of fashion, men of rank, to the threadbare-coated student--eagerly watching the experiments, and all drinking in his words as the young lecturer, fired with his subject, animated with all the charm of which he was so complete a master the dry bones of geology with life and breath, or again brought the study of chemistry, hitherto unget-at-able and out of reach, down to their level. The audience hung on his lips spellbound. The young popular lecturer was caressed and made much of. "Davy, covered with glory," writes a friend at this time, "dines with me to-day." Soon they made him Professor of Chemistry to the Institution. Promotion followed promotion, but each year was a spur to greater exertion. Time would fail to enumerate the steps in his triumphs. A continuous sun seemed to shine upon him. And his strength seemed equal to all demands. Money had never been of much account to him. Now, indeed, he might have had it in abundance had he chosen, by helping forward manufactures with his scientific knowledge, but that was not his aim. His ambition was scientific glory. "To be useful to science and mankind was the pursuit in which he gloried." The years that followed were years full of hard work. In 1812 he was knighted. It seemed as if almost everything he touched were like a gold mine which yielded some new treasure to him. "Science," he said once to a young man anxious to pursue it, "is a harsh mistress, and repays one poorly." But for him she surely rather had "full measure pressed down and running over." And now, when he was about thirty-seven, his thoughts were first turned to the great triumph of his life, the invention that was to make his name famous.