“Have you got a match?” he asked.

“No,” growled the other, and the next instant was on the ground, with Elk’s knee on his chest and the detective’s bony hand around his throat.

“Shout, Frog, and I’ll throttle you,” hissed the detective ferociously.

There was no scuffle, no sound. The thing was done so quickly that, if there were other watchers in the street, they could not have known what had happened, or have received any warning from their comrade’s fate. The man was in the hands of the following detective, gagged and handcuffed, and on his way to the police car, before he knew exactly what tornado had struck him.

“Do you mind if I sing?” said Elk as they turned into the street on the opposite side to that where Mr. Maitland’s late residence was situated.

Without waiting permission Elk broke into song. His voice was thin and flat. As a singer, he was a miserable failure, and Dick Gordon had never in his life listened with so much patience to sounds more hideous. But there would be watchers at each end of the street, he thought, and soon saw that Elk’s precautions were necessary.

Again it was in the shadow of a street-lamp that the sentinel stood—a tall, thickset man, more conscientious in the discharge of his duties than his friend, for Dick saw something glittering in his mouth, and knew that it was a whistle.

“Give me the woild for a wishing well,” wailed Elk, staggering slightly, “Say that my dre-em will come true . . .”

And as he sang he made appropriate gestures. His outflung hand caught the whistle and knocked it from the man’s mouth, and in a second the two sprang at him and flung him face downward on the pavement. Elk pulled his prisoner’s cap over his mouth; something black and shiny flashed before the sentry’s eyes, and a cold, circular instrument was thrust against the back of his ear.

“If you make a sound, you’re a dead Frog,” said Elk; and that portion of his party which had made the circuit coming up at that moment, he handed his prisoner over and replaced his fountain-pen in his pocket.