"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 Mr. 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 mantel-shelf. Let me light it.

"Take care you don't burn your fingers, Or set anything 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