Lazard deftly charged the weapon with three small needles, which he took from a little gold ornament on his watch-fob. The needles were extremely thin, and about three-quarters of an inch long. They were wet when he lifted them from the little trinket, and he exercised scrupulous care in the way he handled them. He did not touch them with his fingers, but fed them into the tube with a pair of tweezers.

Then he fitted a rubber shield over the trigger and slipped it back into his pocket.

The cab was already half-way up Kingsway. He carefully wiped the gold trinket on a piece of cotton-wool, and burned the wool on the floor of the cab. It burned with a bright blue flame that flared up instantly, burned fiercely for a second, and as quickly died.

He tapped the window, and the cab pulled in to the kerb.

"I don't exactly know where Denburh House is, sir," said the driver apologetically.

"All right; you've passed it. I'll walk back," said the Count, and paid him off