“Put down your hat and coat, Mistair Kennedy,” he hissed. “The door has been locked ever since you have been here. Those windows are barred, the telephone wire is cut, and it is three hundred feet to the street. We shall leave you here when the fumes have overcome you. Francois and I can stand them up to a point, and when we reach that point we are going.”

Instead of being cowed Kennedy grew bolder, though I, for my part, felt so weakened that I feared the outcome of a hand-to-hand encounter with either Poissan or Francois, who appeared as fresh as if nothing had happened. They were hurriedly preparing to leave us.

“That would do you no good,” Kennedy rejoined, “for we have no safe full of jewels for you to rob. There are no keys to offices to be stolen from our pockets. And let me tell you—you are not the only man in New York who knows the secret of thermite. I have told the secret to the police, and they are only waiting to find who destroyed Morowitch's correspondence under the letter 'P' to apprehend the robber of his safe. Your secret is out.”

“Revenge! revenge!” Poissan cried. “I will have revenge. Francois, bring out the jewels—ha! ha!—here in this bag are the jewels of Mr. Morowitch. To-night Francois and I will go down by the back elevator to a secret exit. In two hours all your police in New York cannot find us. But in two hours you two impostors will be suffocated—perhaps you will die of cyanogen, like Morowitch, whose jewels I have at last.”

He went to the door into the hall and stood there with a mocking laugh. I moved to make a rush toward them, but Kennedy raised his hand.

“You will suffocate,” Poissan hissed again.

Just then we heard the elevator door clang, and hurried steps came down the long hall.

Craig whipped out his automatic and began pumping the bullets out in rapid succession. As the smoke cleared I expected to see Poissan and Francois lying on the floor. Instead, Craig had fired at the lock of the door. He had shattered it into a thousand bits. Andrews and his men were running down the hall.

“Curse you!” muttered Poissan as he banged the now useless lock, “who let those fellows in? Are you a wizard?”

Craig smiled coolly as the ventilation cleared the room of the deadly cyanogen.