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 apparatus, as we employ it, two india-rubber tubes from this box open into a sort of respirator, which covers the head of the operator, one for the introduction and the other for the expulsion of the air, and the tongue closes one or the other, as the exigencies of inspiration and respiration demand. But I, who have to dare considerable pressure at the bottom of the sea, enclose my head in a helmet, as the divers do, and it is to this that the two tubes are attached.”

“Excellent, Captain Nemo. But the air you carry must be quickly expended; and so soon as it contains more than fifteen per cent. of oxygen it ceases to be respirable.”

“Certainly; but as I have said, the pumps of the Nautilus allow of the stowing of the air under a great pressure, and so the air in the reservoir will last for nine or ten hours.”

“I have no objection to make,” I said. “I only want to know how you can obtain light at the bottom of the ocean.”

“By means of the Ruhmkorff apparatus. If the first be carried on the back, the other is fixed to the chest. It is composed of a Bunzen pile, which acts, not with bi-chromate of potash, but with sodium. An induction bobbin collects the electricity produced, and directs it towards a lamp of peculiar construction. In this lamp is a glass serpentine, which contains only a residuum of carbonic acid gas. When the apparatus is at work the gas becomes luminous, and gives forth a white and steady flame. Thus provided, I can both breathe and see.”

“Captain Nemo, to all my objections you return K 2