The door was shut. The old man rose wearily and hobbled downstairs, no doubt to fetch oil or whatever was used for the lamp.
Kenneth felt that the time had come for action. The mention of the lamp left no doubt in his mind of the work on which the occupants of the room were engaged. Waiting until the old man had reached the foot of the lower staircase, he stole down to the room where he had left his companions and told them in a few whispered words what he had discovered. They removed their boots and stood behind the door, prepared to follow the man when he came up again.
In a few minutes he returned. They waited until he had ascended the upper staircase, then followed him noiselessly, saw him enter the room, and crept along to the door, drawing their revolvers. From within the room came the smell of acetylene gas. Standing back against the wall, they waited for the reopening of the door. As soon as the old man reappeared, they started forward, pointing their revolvers at him, pushed him before them and entered the room.
There was an exclamation, a moment of confusion.
"Hands up, or I fire!" cried Kenneth in German.
There were four men in the room, three seated at a table drinking beer, the fourth occupied with a steel lever operating a disc that worked from side to side in front of a bright bull's-eye lamp. Kenneth's warning had checked a movement on the part of two of the seated men towards their coat pockets. The man at the lamp, who had faced round at the sudden intrusion, was quicker than his companions, and drew his revolver at the moment of turning. But as he was raising his hand Harry fired. His revolver fell to the floor with a crash, and with a curse he clasped his broken wrist with the other hand.
The three others had fallen back into their chairs. A stream of beer from an overturned mug trickled from the table to the floor, for one tense moment the only sound in the room. The men's faces were pale and contorted with fear. They sat, limp, with no spirit for resistance, recognizing that the game was up.
Kenneth and Harry glowed with a quiet satisfaction. Ginger was more demonstrative.
"Blest if I haven't got him at last!" he exclaimed, smiling triumphantly at one of the prisoners. "It's the chap that downed me when I was sitting on that aeroplane."
"Monsieur Obernai is unfortunate in his friends," said Kenneth.