The French, from economical reasons, early gave their attention to the use of seed oils, and the first developments of the moderator lamp of the drawing-room are exclusively French. There were many difficulties in the way of applying it to lighthouses until it had been greatly simplified, because the fact of the carcel lamp being a somewhat complicated piece of machinery was against its use in places where, if anything went wrong, it might be a month or two before the weather would admit of the light-keepers being relieved, and give them an opportunity of exchanging old lamps for new. The thing was done at last by a simple but very beautiful adjustment of the argand reservoir, under which the prime condition for all good combustion was attained, namely, that the oil just about to be burnt, should be rarefied and prepared for burning by the action of the heat of that which is at the moment being consumed. And so great is the quantity of oil used in the three kingdoms, that this change from sperm to rapeseed oil must have made a saving of many thousands a year. But if oil from its portability and comparative simplicity has become the standard material for light in lighthouses, and has been the object of a thousand and one nice adaptations in regard to its preparation and the machinery by which it is consumed, the attention of very able men has been given to other sources of illumination. One of these was known as the Bude light, and consisted of jets of oxygen introduced into the centre of oil wicks, producing an intense 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.