“He means something he heard at the Royal Institution,” observed Mrs. Wilkinson. “He reads a great deal about chemistry, and he attended Professor Faraday’s lectures there on the chemical history of a candle, and has been full of it ever since.”
“Now, you sir,” said Uncle Bagges, “come you here to me, and tell me what you have to say about this chemical, eh? or comical; which? this comical chemical history of a candle.”
“He’ll bore you, Bagges,” said Mrs. Wilkinson. “Harry, don’t be troublesome to your uncle.”
“Troublesome! Oh, not at all. He amuses me. I like to hear him. So let him teach his old uncle the comicality and chemicality of a farthing rushlight.”
“A wax candle will be nicer and cleaner, uncle, and answer the same purpose. There’s one on the mantle-shelf. Let me light it.”
“Take care you don’t burn your fingers, or set any thing on fire,” said Mrs. Wilkinson.
“Now, uncle,” commenced Harry, having drawn his chair to the side of Mr. Bagges, “we have got our candle burning. What do you see?”
“Let me put on my spectacles,” answered the uncle.
“Look down on the top of the candle around the wick. See, it is a little cup full of melted wax. The heat of the flame has melted the wax just round the wick. The cold air keeps the outside of it hard, so as to make the rim of it. The melted wax in the little cup goes up through the wick to be burnt, just as oil does in the wick of a lamp. What do you think makes it go up, uncle?”