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 combustion, which turned steel wire into fireworks, but requiring great management to avoid smoking and charring. It was finally regarded as unsuitable on account of the manufacture of the gas and its niceties of chemical manipulation.

The Lime lights, of which there are several, are substantially the same in this, that oxygen and hydrogen gases have to be made (in the vicinity of gas-works, the common gas will do for the hydrogen) and are burnt together upon lime or some analogous preparation; and there is a magnificent adaptation of the Electric light at this moment at the South Foreland.

The first electric lights were galvanic. The light, developed between carbon points, was generated by a galvanic battery. Flickering, intermittent, and uncertain, the light was yet sufficiently astonishing, and when it came to be discovered that the residuum from the decomposition was valuable for making costly colours, "The Electric Power Light and Colour Company" offered to sell the mere light at a very low rate; but the difficulties in the way were insuperable, the manipulation of the batteries was somewhat nice and markedly unhealthy, the flickering was objectionable, and the light, though intense, was so extremely minute that the shadows of the framework of the lantern-glasses widened outwards in a way that would have covered the horizon seaward with broad bands of dark.

But the matter was not to stop here. In 1831 it had been discovered by Faraday that when a piece of soft iron surrounded by a metallic wire was passed by the poles of a magnet, an electric current was produced in the wire, which could be exalted so as to give a spark; and upon this hint an apparatus has been constructed, consisting of an accumulation of powerful magnets and iron cores with surrounding coils. This apparatus, driven by steam-engines, and fitted with a subtle ingenuity of resource always tending to simplicity that seems a marked feature in the mind of the patentee, is, as we have said, at this moment at work, and very glorious it is to the eye of the observer; a piece of sunlight poured out upon the night.

The chief point to be determined is its power over fogs. That any light will penetrate through some fogs is out of the question. The Sun himself can't do it. But the artificial light that can hold out longest and pierce the farthest is clearly the light at all costs for the turning points in the great ocean highways.

A success of this kind would create something of a revolution in a branch of lighthouse art on which a vast amount of ingenuity and even genius has been expended; that is, the apparatus by which the light should be exhibited. There may be divisions among scientific men as to the abstract nature and action of light, but sufficient of its secondary laws are known to make various arrangements in regard to the management of a generated light most valuable.

The old plan known in scientific nomenclature as the Catoptric system is by reflection.