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 Faraday could turn completely round in her own length. Moreover, as the ship could steam forwards or backwards with equal ease, it became unnecessary to pass the cable forward before hauling it in, if a fault were discovered in the part submerged: the motion of the ship had only to be reversed, the stern rudder fixed, and the bow rudder turned, while a small engine was employed to haul the cable back over the stern drum, which had been used a few minutes before to pay it out.

The first expedition of the Faraday was the laying of the Direct United States cable in the winter of 1874 a work which, though interrupted by stormy weather, was resumed and completed in the summer of 1875. She has been engaged in laying several Atlantic cables since, and has been fitted with the electric light, a resource which has proved of the utmost service, not only in facilitating the night operations of paying-out, but in guarding the ship from collision with icebergs in foggy weather off the North American coast.

Mention of the electric light brings us to an important act of the inventor, which, though done on behalf of his brother Werner, was pregnant with great consequences. This was his announcement before a meeting of the Royal Society, held on February 14, 1867, of the discovery of the principle of reinforcing the field magnetism of magneto-electric generators by part or the whole of the current generated in the revolving armature—a principle which has been applied in the dynamo-electric machines, now so much used for producing electric light and effecting the transmission of power to a distance by means of the electric current. By a curious coincidence the same principle was enunciated by Sir Charles Wheatstone at the very same meeting; while a few months previously