Says Prof. E. N. Horsford of Cambridge, Mass., in the admirable life of Morse written by Dr. Samuel Irenæus Prime: "He knew generally, when he stepped on board the Sully, in 1832, that a soft-iron horseshoe-shaped bar of iron could be rendered magnetic while a current of galvanic electricity was passing through a wire wound round it; and he knew that electricity had been transmitted, apparently instantaneously, through wires of great length, by Franklin and others.... In the leisure of ship-life the idea of a _recording_ electric telegraph seized Professor Morse's mind, and he gave expression to his conviction that it was _possible_. As it was possible to _dispatch_ and to _arrest_ the current, he conceived that some device could be found for compelling it to manifest itself by this intermittent action, and produce a record. "He knew, for he had witnessed it years before, that by means of a battery and an electro-magnet reciprocal motion could be produced. He knew that the force which produced it could be transmitted along a wire. He _believed_ that the battery current could be made, through an electro-magnet, to produce physical effects at a _distance_. He saw in his mind's eye the existence of an agent and a medium by which reciprocal motion could be not only produced, but _controlled_, at a _distance_. The question that addressed itself to him at the outset was naturally this: 'How can I make use of the simple up-and-down motion of opening and closing a circuit to write an intelligible message at one end of a wire, and at the same time print it at the other?'... "Like many a kindred work of genius, it was in nothing more wonderful than in its simplicity. First, he caused a continuous ribbon or strip of paper to move under a pencil by clock-work, that could be wound up. The paper moved horizontally. The pencil moved only up and down; when resting on the paper it made a mark--if for an instant only, a dot; if for a longer time, a line. When lifted from the paper it left a blank.... The grandeur of this wonderful alphabet of dots, lines, and spaces has not been fully appreciated.... "Not one of all the brilliant scientific men who have attached their names to the history of electro-magnetism had brought the means to produce the practical registering telegraph. Some of them had ascended the tower that looked out on the field of conquest. Some of them brought keener vision than others. Some of them stood higher than others; but the genius of invention had not recognized them. There was needed an inventor." As soon as Morse left the ship Sully, and met his brothers Richard and Sidney, he told them that he had made an important invention, "one that would astonish the world, and of the success of which he was perfectly sanguine." He became an inmate of Richard's house, living there several months.