Such was the state of things when a revolution in the art of printing was effected which, in importance, can be compared only to the original discovery of printing. In fact, since the days of Gutenberg to the present hour, there has been only one great revolution in the art, and that was the introduction of steam printing in 1814. The neat and elegant, but slow-moving Stanhope press, was after all but little in advance of its rude prototype of the fifteenth century, the chief features of which it preserved almost without alteration. The steam printing machine took a leap ahead that placed it at such a distance from the printing press, that they are hardly to be recognised as the offspring of the same common stock. All family resemblance has died out, although the printing machine is certainly a development of the little screw press. Of the revolution of 1814, which placed the printing machine in the seat of power, _vice_ the press given over to subordinate employment, Mr. John Walter of the _Times_ was the prominent and leading agent. But for his foresight, enterprise, and perseverance, the steam machine might have been even now in earliest infancy, if not unborn. Familiar as the invention of the steam printing machine is now, in the beginning of the present century it shared the ridicule which was thrown upon the project of sailing steam ships upon the sea, and driving steam carriages upon land. It seemed as mad and preposterous an idea to print off 5000 impressions of a paper like the _Times_ in one hour, as, in the same time, to paddle a ship fifteen miles against wind and tide, or to propel a heavily laden train of carriages fifty miles. Mr. Walter, however, was convinced that the thing could be done, and lost no time in attempting it. Some notion of the difficulties he had to overcome, and the disappointments he had to endure, while engaged in this enterprise, may be gathered from the following extracts from the biography of Mr. Walter, which appeared in the _Times_ at the time of his death in July 1847:--