Concurrently with the development of steam transport upon land and sea a new and striking addition to the facilities of human intercourse arose out of the investigations of Volta, Galvani and Faraday into various electrical phenomena. The electric telegraph came into existence in 1835. The first underseas cable was laid in 1851 between France and England. In a few years the telegraph system had spread over the civilized world, and news which had hitherto travelled slowly from point to point became practically simultaneous throughout the earth. These things, the steam railway and the electric telegraph, were to the popular imagination of the middle nineteenth century the most striking and revolutionary of inventions, but they were only the most conspicuous and clumsy first fruits of a far more extensive process. Technical knowledge and skill were developing with an extraordinary rapidity, and to an extraordinary extent measured by the progress of any previous age. Far less conspicuous at first in everyday life, but finally far more important, was the extension of man’s power over various structural materials. Before the middle of the eighteenth century iron was reduced from its ores by means of wood charcoal, was handled in small pieces, and hammered and wrought into shape. It was material for a craftsman. Quality and treatment were enormously dependent upon the experience and sagacity of the individual iron-worker. The largest masses of iron that could be dealt with under those conditions amounted at most (in the sixteenth century) to two or three tons. (There was a very definite upward limit, therefore, to the size of cannon.) The blast-furnace rose in the eighteenth century and developed with the use of coke. Not before the eighteenth century do we find rolled sheet iron (1728) and rolled rods and bars (1783). Nasmyth’s steam hammer came as late as 1838.