Perhaps it was this very freedom of thought which debarred him from enlisting other men as collaborators in his researches. His one assistant for thirty years, Sergeant Anderson, was indeed invaluable to him for his quality of implicit obedience. Other helpers in the laboratory he had none. Apparently he found his researches to be of too individual a character to permit him to deputise any part of his work. He was never satisfied when told about another’s experiment; he must perform it for himself. Often a discovery arose from some chance or trivial incident of an otherwise unsuccessful experiment. The power of “lateral vision,” which Tyndall has so strongly emphasised, was a prime factor in his successes. That power could not be delegated to any mere assistant. Many times did outsiders approach him, thinking to bring new facts to his notice; never, save on the solitary occasion when a Mr. William Jenkin drew his attention to the “extra-current” spark seen on the breaking of an electric circuit, did such novelties turn out to be really new. Alleged discoveries thus brought to him merely plagued him. He thought that anyone who had the wit to observe any really new phenomenon would be the person best qualified to work it out. His method was to work on alone, dwelling amidst his experiments until the mind, familiarising itself with the facts, was ready to suggest their correlations. It was sometimes urged against him as a complaint that he never took up any younger man to train him as his successor, even as Davy had taken up himself and trained him in scientific work. One of the miscellaneous notes, found after his death, throws some light on this:-- It puzzles me greatly to know what makes the successful philosopher. Is it industry and perseverance with a moderate proportion of good sense and intelligence? Is not a modest assurance or earnestness a requisite? Do not many fail because they look rather to the renown to be acquired than to the pure acquisition of knowledge, and the delight which the contented mind has in acquiring it for its own sake? I am sure I have seen many who would have been good and successful pursuers of science, and have gained themselves a high name, but that it was the name and the reward they were always looking forward to--the reward of the world’s praise. In such there is always a shade of envy or regret over their minds, and I cannot imagine a man making discoveries in science under these feelings. As to Genius and its power, there may be cases; I suppose there are. I have looked long and often for a genius for our Laboratory, but have never found one. But I have seen many who would, I think, if they had submitted themselves to a sound self-applied discipline of mind, have become successful experimental Philosophers. To Dr. Becker he wrote: