“And so,” resumed Harry, “hydrogen, you know, uncle, is part of water, and just one-ninth part.”
“As hydrogen is to water, so is a tailor to an ordinary individual, eh?” Mr. Bagges remarked.
“Well, now, then, uncle, if hydrogen is the tailor’s part of the water, what are the other eight parts? The iron-turnings used to make hydrogen in the gun-barrel, and rusted, take just those eight parts from the water in the shape of steam, and are so much the heavier. Burn iron turnings in the air, and they make the same rust, and gain just the same in weight. So the other eight parts must be found in the air for one thing, and in the rusted iron turnings for another, and they must also be in the water; and now the question is, how to get at them?”
“Out of the water? Fish for them, I should say,” suggested Mr. Bagges.
“Why, so we can,” said Harry. “Only instead of hooks and lines, we must use wires—two wires, one from one end, the other from the other, of a galvanic battery. Put the points of these wires into water, a little distance apart, and they instantly take the water to pieces. If they are of copper, or a metal that will rust easily, one of them begins to rust, and air-bubbles come up from the other. These bubbles are hydrogen. The other part of the water mixes with the end of the wire and makes rust. But if the wires are of gold, or a metal that does not rust easily, air-bubbles rise from the ends of both wires. Collect the bubbles from both wires in a tube, and fire them, and they turn to water again; and this water is exactly the same weight as the quantity that has been changed into the two gases. Now, then, uncle, what should you think water was composed of?”
“Eh? well—I suppose of those very identical two gases, young gentleman.”
“Right, uncle. Recollect that the gas from one of the wires was hydrogen, the one-ninth of water. What should you guess the gas from the other wire to be?”
“Stop—eh?—wait a bit—eh—oh!—why, the other eight-ninths, to be sure.”
“Good again, uncle. Now this gas that is eight-ninths of water is the gas called oxygen that I mentioned just now. This is a very curious gas. It won’t burn in air at all itself, like gas from a lamp, but it has a wonderful power of making things burn that are lighted and put into it. If you fill a jar with it—”
“How do you manage that?” Mr. Bagges inquired.