“Fancy using such dirty stuff!” said Mary.
“The manure in it makes it stick, just as hair does in mortar. Clay would crack with the heat. So you see, dear, there’s nothing so dirty or so common that it may not be of some use in the world.”
“How do you know when they are cooked enough?” asked Charley.
“I’ll show you,” said Mr. Sands, and he immediately led us to a small door, which opened some way up the kiln.
“This is called the crown,” said Mr. Sands.
It was a flat surface, with four holes which showed the red heat below, and looked like little volcanoes in a good temper.
“Do you see those iron rods hanging like walking-sticks in the furnace?” asked our guide. “Well, those are called trials, and at the end of each is a lump of clay and glaze. If the glaze is burnt enough we suppose that the whole batch is done, but we sometimes make a mistake and spoil a lot.”
“What is done next?” asked Charley.
“If they are properly burnt, they are allowed to cool gradually, and are then ready for sale.”
By this time all were pretty well tired, and so they said good morning to Mr. Sands and went home.