Smoke puffed in a sudden cloud, obscuring the whole opening. From behind it came a harsh mocking laugh.
Before the sound died out, Don Winslow slammed his rifle barrel into the crack of the closing mirror, jamming its machinery. At the same time there came the clang of a steel door somewhere inside the secret room.
“They’re gone!” yelped Red Pennington. “Quick, Suzette! Which way can we follow ’em?”
“Back! Get back, Monsieur!” cried the little French maid, tugging at his sleeve. “That smoke is deadly poison. Quick, everyone—put on the gas masks and come away!”
“She’s right, Red!” clipped Don Winslow, whipping out his own mask. “Clear out of here before something worse happens! I’ll be with you as soon as I get my gun loose.”
The smoke had spread out some distance from the jammed doorway, making objects near it indistinct. As his friends moved back, Don Winslow plunged straight into it. For a few moments his figure vanished completely.
Just as Red was about to go back for him he reappeared, carrying not only his rifle but a bundle of black leather-covered books. Without lifting his mask, he motioned the others on, away from the spreading smoke.
For Suzette, their retreat was barely in time. Unprotected by a gas mask, the courageous French girl had refused to leave the room before Don appeared. Now, reeling from a slight dose of the poison, she led them through a panel in the farther wall.
In the clean air of an adjoining room she motioned her companions to remove their masks.
“It is over now, my friends,” she said faintly, as Red steadied her in the grip of a muscular arm. “We have lost the Scorpion and his so evil lieutenant, but we have failed in nothing else, I think. Thanks to Commander Winslow, we have the evidence which will convict many of our enemies of their hidden crimes!”