mixes with the oxygen and weakens it."

"Makes a sort of gaseous grog of it, eh?" said Mr. Bagges. "But how is
that proved?"

"Why, there is a gas, called nitrous gas, which, if you mix it with
oxygen, takes all the oxygen into itself, and the mixture of the
nitrous gas and oxygen, if you put water with it, goes into the water.
Mix nitrous gas and air together in a jar over water, and the nitrous
gas takes away the oxygen, and then the water sucks up the mixed
oxygen and nitrous gas, and that part of the air which weakens the
oxygen is left behind. Burning phosphorus in confined air will also
take all the oxygen from it, and there are other ways of doing the
same thing. The portion of the air left behind is called nitrogen. You
wouldn't know it from common air by the look; it has no color, taste,
nor smell, and it won't burn. But things won't burn in it, either;
and anything on fire put into it goes out directly. It isn't fit to
breathe, and a mouse, or any animal, shut up in it, dies. It isn't
poisonous, though; creatures only die in it for want of oxygen. We
breathe it with oxygen, and then it does no harm, but good: for if
we breathed pure oxygen, we should breathe away so violently, that
we should soon breathe our life out. In the same way, if the air were
nothing but oxygen, a candle would not last above a minute.

"What a tallow-chandler's bill we should have!" remarked Mrs.
Wilkinson.

"'If a house were on fire in oxygen,' as Professor Faraday said,
'every iron bar, or rafter, or pillar, every nail and iron tool,
and the fire-place itself; all the zinc and copper roofs, and leaden