ome chemical or other physical mystery. Master
Wilkinson had now attained to the ability of making experiments; most of
which, involving combustion, were strongly deprecated by the young
gentleman's mamma; but her opposition was overruled by Mr. Bagges, who
argued that it was much better that a young dog should burn phosphorus
before your face than let off gunpowder behind your back, to say nothing
of occasionally pinning a cracker to your skirts. He maintained that
playing with fire and water, throwing stones, and such like boys' tricks,
as they are commonly called, are the first expressions of a scientific
tendency--endeavors and efforts of the infant mind to acquaint itself with
the powers of Nature.

His own favorite toys, he remembered, were squibs, suckers, squirts, and
slings; and he was persuaded that, by his having been denied them at
school, a natural philosopher had been nipped in the bud.

Blowing bubbles was an example--by-the-by, a rather notable one--by which
Mr. Bagges, on one of his scientific evenings, was instancing the affinity
of child's play to philosophical experiments, when he bethought him Harry
had said on a former occasion that the human breath consists chiefly of
carbonic acid, which is heavier than common air. How then, it occurred to
his inquiring, though elderly mind, was it that soap-bladders, blown from
a tobacco-pipe, rose instead of sinking? He asked his nephew this.

"Oh, uncle!" answered Harry, "in the first place, the air you blow bubbles
with mostly comes in at the nose and goes out at the mouth, without having
been breathed at all. Then it is warmed by the mouth, and warmth, you
know, makes a measure of air get larger, and so lighter in proportion. A
soap-bubble rises for the same reason that a fire-balloon rises--that is,
because the air inside of it has been heated, and weighs less than the
same sized bubbleful of cold air."

"What, hot breath does!" said Mr. Bagges. "Well, now, it's a curious
thing, when you come to think of it, that the breath should be hot--indeed,
the warmth of the body generally seems a puzzle. It is wonderful, too, how
the bodily heat can be kept up so long as it is. Here, now, is this
tumbler of hot grog--a mixture of boiling water, and what d'ye call it, you
scientific geniuses?"

"Alcohol, uncle."

"Alcohol--well--or, as we used to say, brandy. Now, if I leave this tumbler
of brandy-and-water alone--"

"_If_ you do, uncle," interposed his nephew,