"Well?" the latter said.

"Good Lord! no wonder you've been plucked three times!" Despard cried. "Don't you know what this stuff is?"

Rupert examined it again. "Rather like pitch-blende."

"Yes—something," Despard sneered.

A sharp cry escaped Rupert's lips. He bent down and examined the black, sticky substance more carefully.

"It is pitch-blende!"

"Extinguish the light," Despard said sharply.

Rupert obeyed. A long time they stood in the darkness. Presently Despard commenced to dig and scrape the surface and sides of the tunnel. After a little while he struck a match and re-lit the lantern.

"That was expecting rather too much," he whispered.

They collected the pitch-blende they had found, and putting it into his handkerchief Despard dropped it into his pocket.