[2] Ruhmkorff's apparatus consists of a Bunsen pile worked with bichromate of potash, which makes no smell; an induction coil carries the electricity generated by the pile into communication with a lantern of peculiar construction; in this lantern there is a spiral glass tube from which the air has been excluded, and in which remains only a residuum of carbonic acid gas or of nitrogen. When the apparatus is put in action this gas becomes luminous, producing a white steady light. The pile and coil are placed in a leathern bag which the traveller carries over his shoulders; the lantern outside of the bag throws sufficient light into deep darkness; it enables one to venture without fear of explosions into the midst of the most inflammable gases, and is not extinguished even in the deepest waters. M. Ruhmkorff is a learned and most ingenious man of science; his great discovery is his induction coil, which produces a powerful stream of electricity. He obtained in 1864 the quinquennial prize of 50,000 franc reserved by the French government for the most ingenious application of electricity. The tools comprised two pickaxes, two spades, a silk ropeladder, three iron-tipped sticks, a hatchet, a hammer, a dozen wedges and iron spikes, and a long knotted rope. Now this was a large load, for the ladder was 300 feet long. And there were provisions too: this was not a large parcel, but it was comforting to know that of essence of beef and biscuits there were six months' consumption. Spirits were the only liquid, and of water we took none; but we had flasks, and my uncle depended on springs from which to fill them. Whatever objections I hazarded as to their quality, temperature, and even absence, remained ineffectual. To complete the exact inventory of all our travelling accompaniments, I must not forget a pocket medicine chest, containing blunt scissors, splints for broken limbs, a piece of tape of unbleached linen, bandages and compresses, lint, a lancet for bleeding, all dreadful articles to take with one. Then there was a row of phials containing dextrine, alcoholic ether, liquid acetate of lead, vinegar, and ammonia drugs which afforded me no comfort. Finally, all the articles needful to supply Ruhmkorff's apparatus. My uncle did not forget a supply of tobacco, coarse grained powder, and amadou, nor a leathern belt in which he carried a sufficient quantity of gold, silver, and paper money. Six pairs of boots and shoes, made waterproof with a composition of indiarubber and naphtha, were packed amongst the tools. "Clothed, shod, and equipped like this," said my uncle, "there is no telling how far we may go."