Byers was at the nozzle. The little man had stuck it out gamely. Only four of the original party were still working. The others had been relieved and sent to the surface.

McClintock had just returned from the shaft where he had been with a man overcome by the heat. He was for the moment the freshest man in the group.

“Two volunteers to search the crosscut while the rest hold back the fire,” called Carstairs.

“I’ll go,” said a Maine lumberjack.

“Same here,” added Hugh.

They waited, watching for a chance to plunge into the side tunnel when the fire was momentarily low.

“Now,” said McClintock, and he dived at the opening in the wall.

The lumberjack followed him. So intense was the heat at the entrance to the crosscut that a little pool of water on the rock floor was boiling angrily. As they pushed deeper into it the heat decreased.

Hugh shouted. A voice answered his call.

He moved forward and presently stumbled over a body.