generating a current by means of heat, and since then a variety of thermo-piles have been invented, some of which have proved of considerable advantage.
Wheatstone abandoned his idea of transmitting intelligence by the mechanical vibration of rods, and took up the electric telegraph. In 1835 he lectured on the system of Baron Schilling, and declared that the means were already known by which an electric telegraph could be made of great service to the world. He made experiments with a plan of his own, and not only proposed to lay an experimental line across the Thames, but to establish it on the London and Birmingham Railway. Before these plans were carried out, however, he received a visit from Mr. Fothergill Cooke at his house in Conduit Street on February 27, 1837, which had an important influence on his future.
Mr. Cooke was an officer in the Madras army, who, being home on furlough, was attending some lectures on anatomy at the University of Heidelberg, where, on March 6, 1836, he witnessed a demonstration with the telegraph of Professor Möncke, and was so impressed with its importance, that he forsook his medical studies and devoted all his efforts to the work of introducing the telegraph. He returned to London soon after, and was able to exhibit a telegraph with three needles in January, 1837. Feeling his want of scientific knowledge, he consulted Faraday and Dr. Roget, the latter of whom sent him to Wheatstone.
At a second interview, Mr. Cooke told Wheatstone of his intention to bring out a working telegraph, and explained his method. Wheatstone, according to his own statement, remarked to Cooke that the method would not act, and produced his own experimental telegraph. Finally, Cooke proposed that they should enter into a partnership, but Wheatstone was at first
