The tunnel was rapidly filling with smoke, and through the white drifts of it they looked into the lighted cellar beyond.

They would run out at last, gasping for breath and blinded by the smoke, to be shot down in a perfect light.

So much was clear.
"Now back to the wall and try to find that door," said Ronicky.
Jerry had already turned.

In a moment they were back and tearing with their fingers at the sham wall, kicking loose fragments with their feet.
All the time, while they cleared a larger and larger space, they searched feverishly with the electric torch for some sign of a knob which would indicate a door, or some button or spring which might be used to open it.

But there was nothing, and in the meantime the smoke was drifting back, in more and more unendurable clouds.
"I can't stand much more," declared Jerry at length.
"Keep low.