Stirling widened the door by a steady pull with his fingers, and stared beyond the Russian to where an opening showed in the bulkhead. This opening marked the way to the engine room and the after part of the ship.
Bunker doors and slides showed to port and starboard, and the coal lay piled where the passers had shovelled it. A Russian tossed away his cigarette, seized a scoop shovel, and stepped to the after door of the forward furnace. The glare which filled the stokehold as he opened the door gave Stirling an opportunity.
Risking all on the venture, he flung wide the bulkhead door which led from the lazaret and dashed across the scattered coal, reaching the opening to a spare bunker on the starboard side of the hold before he was discovered. Then a Russian shouted a warning, and the chief of the stokehold crew swung from the furnaces and stared through the half light.
Stirling brushed aside the lunging form of a revolutionist, and struck a second Russian a swinging blow beneath the ear. Plunging on, he gained the door which led to the engine room as a slice bar was hurled in his direction.
He wheeled at the door and braced himself. The Russian he had struck was slowly rising from the iron plate before the spare bunker, and a form swung from the reflection of light which streamed out of an ash box and lunged forward. Stirling called a warning as he bent, twisted, and worked his way through the bulkhead door until he reached the alleyway which led to the engine room.
Flashing crank shafts and the polished glow of metal blinded him. Men were on the gratings and halfway up the ladder which led to the deck companion. Stirling dodged around the first and second intermediate cylinders, rested a hand on the huge low-pressure cylinder; then he dropped to one knee, squirmed beneath the tail shaft, and started crawling down the shaft alley.
The Russians had been too startled to prevent this manœuvre, but now they came aft with torches and pinch bars. The glow from the overhead sun which streamed through the deck light brought out the details of the shaft alley as far aft as the second coupling. Behind this was a narrow pit compressed on each side by heavy planking and sloping at the bottom into the fan-shaped overhang of the Pole Star's stern.
Stirling worked his way aft to the thrust bearings, which were three in number. Here the pit was dark and damp, and he turned and glanced forward. The faint light which marked the outlines of the shaft alley grew stronger as he waited.
A burly form moved within the gloom, then another man joined the first Russian. Hammer blows sounded, and the light vanished as if a shade had been drawn. Stirling, with every sense alert, guessed the reason for the darkness. The revolutionists in the engine room had brought aft a number of sheets of boiler plate, and these they had erected about the tail shaft where it entered the engine room.
A grim smile creased Stirling's lips as he waited. The way now was barred by three-eighth-inch iron; he was a prisoner in the pit.