Now come into the laboratory with me and see how it is done." In the centre of the workroom was an instrument like a huge vice, with two large brass-coloured plates, and a great steel screw for bringing them together.

Numerous wires ran into these metal plates, and were attached at the other end to the rows of dynamic machines.

Beneath was a glass stand, which was hollowed out in the centre into a succession of troughs.
"You will soon understand all about it," said Raffles Haw, throwing off his coat, and pulling on a smoke-stained and dirty linen jacket.

"We must first stoke up a little." He put his weight on a pair of great bellows, and an answering roar came from the furnace.

"That will do.