Clambering up once more to the great valve, he hammered it until the rust that stiffened it was loosened. Then he struggled with the valve until it was closed.
"We'll see what happens!" he muttered.
Returning to the ground, he set to work to break the green metal fetters upon Agnes' wrists and ankles, using the broken lever as hammer and file.
For the greater part of six days he toiled at that task, while the great hammer rose slowly. But the green metal seemed very hard. One arm was free at the end of the second day, the other on the fourth. He had one ankle loose on the morning of the sixth day. But as evening came on, and the great hammer reached the top of its stroke, the fourth chain still defied him.
Before sunset, a swarm of the monsters appeared, wheeling on green wings. He was forced to leave the work, hiding his improvised file.
Agnes still lay across the anvil, to conceal from the monsters the fact that the chains were broken. Larry sat close beside her, nursing hands that were blistered and sore from his days of filing at the chains.
A sudden clatter came from the huge mechanism above them, and a sharp hiss of steam, which became louder.
"It works!" Larry whispered to Agnes. "The old valve held, and the steam can't get into the cylinder to smash us! But Allah knows what will happen when the pressure rises in that old steam chest!"
Darkness came. Dusk swallowed the wheeling machine-monsters. All night Larry and Agnes waited silently, together on the great anvil, listening to the hissing of steam from above, which was slowly becoming a shrill monotonous scream; monotonous, always higher, shriller.
The "sun" rose again. Still the green-winged monsters wheeled about. They came in glittering swarms, thousands of them. They came nearer the machine now, and flew about more swiftly, is if excited.