“When I consider the variety of theories that may be formed on the slender foundation of one or two facts, I am convinced that it is the business of the true philosopher to avoid them altogether. It is more laborious to accumulate facts than to reason concerning them; but one good experiment is of more value than the ingenuity of a brain like Newton’s.” About the same time he wrote:-- “I was perhaps wrong in publishing, with such haste, a new theory of chemistry. My mind was ardent and enthusiastic. I believed that I had discovered the truth. Since that time my knowledge of facts is increased--since that time I have become more sceptical.” In the October of the same year he wrote:-- “Convinced as I am that chemical science is in its infancy, that an infinite variety of new facts must be accumulated before our powers of reasoning will be sufficiently extensive, I renounce my own particular theory as being a complete arrangement of facts: it appears to me now only as the most _probable_ arrangement.” By the end of the year the repentance was complete, and recantation followed. In a letter which appeared in Nicholson’s Journal in February, 1800, he corrects some of the errors into which he had fallen, and says, “I beg to be considered as a sceptic with regard to my own particular theory of the combinations of light, and theories of light in general.” To the end of his days Davy never forgot the lesson which his earliest effort had taught him; and there is no question that the memory of it acted as a salutary check on the exuberance of his fancy and the flight of his imagination. The wound to his self-love was, however, never wholly healed. Nothing annoyed him more than any reference to Beddoes’s book, and he declared to Dr. Hope that he would joyfully relinquish any little glory or reputation he might have acquired by his later researches were it possible to withdraw his share in that work and to remove the impression he feared it was likely to produce.