He was peering through a window that faced toward the lake. Out of the obscurity of a mist arisen from the lake emerged dark movement, and the movement resolved itself into a black daub that bore resemblance to the shape of a man. It was followed by a second black daub and by a third. Potter watched them, every nerve tense as the strings of a violin. Were they his own men walking about on sentry? He could not tell. He stepped softly to the door at the opposite side of the building, opened it silently, crept out, and made his way with cat-tread around the corner, there to wait, crouching.

The black daubs stole closer. There was not even a whisper. One of them knelt beside the hangar. There was a slight sound—the ignition of a match—a shaded glow—then a tiny splutter.... Potter knew. His guard had been passed; the enemy had set its bomb, had lighted its fuse. He arose and leaped upon the kneeling man, nor did he know that as he leaped he shouted.

The man upon whom he had sprang, surprised though he was, resolved into dynamic action—soundless action. Locked together they rolled over and over. Potter felt the impact as another man leaped upon them—but that other, in the murk of the night and the fog, could not tell friend from foe. Again Potter shouted. There were answering shouts. One antagonist tore away and plunged into the mist; the other, thrusting a savage knee against Potter’s chest, broke the grip of his arms and rolled out of reach. Both sprang to their feet, one in flight, the other in pursuit. But Potter stopped. He remembered. Close beside him spluttered that fuse. He leaped upon it, seized it, hurled the deadly thing toward which that spark was crawling, far in the direction of the lake.... Now he was surrounded by men—his own men.... And then came a mighty cough, as if the universe itself had coughed with all the strength of its hidden forces. There was an instant of light and fire, the impact of an irresistible energy. Stunned, deafened, blinded, Potter was hurled to the ground....

“My Gawd!...” said a voice.

Potter struggled to his feet and stood reeling. “Are you there?... Is any one hurt?” he asked.

The men crowded about him, shaken, trembling. They went inside and stood staring at one another.

“My Gawd!... said Cockney Tom, again.

“They got through us,” Cassidy said, stupidly.

“Most got yuh,” Mort said, and cursed, “and us standin’ around like bats.”

“It’s all right,” Potter said, unsteadily. “It didn’t come off.”