“This will do nicely, lads,” the officer said. “We’ll take a little rest, and then we’ll lower the explosive.”
Some of the men fished out blackened pipes and had a short smoke. Then, at a word from the officer, they knocked out the ashes and proceeded to work.
Long ropes were swung around the cans of TNT, of which they had two, and then Mr. Mayhew very carefully adjusted the time fuses.
“That will give us two hours to get away,” he remarked. “If we can’t make the ship in that time, we’ll deserve to be blown up. Lower away, men, and we’ll be on our way.”
Hand over hand the men lowered the explosive into the deep green chasm. It was a long time before the cans stopped descending, but stop they did at last, and the men drew up the ropes. These were quickly coiled, and then the little party started back for their boat at a sharp clip. They knew that they had plenty of time, and yet the thought of that TNT buried in the heart of the berg destroyed all desire to linger and thus lessen the hardships of their departure.
About half the distance back had been covered when suddenly, as they were skirting around a crevasse, Joe slipped on a smooth slope of ice and with a startled cry disappeared over the edge of the abyss.
For a moment all were stunned by the accident. Then, at the risk of their own lives, Bob and Herb rushed to the edge and peered over. But the sun, reflecting on the glistening wall, made it impossible to see far, and they could make out no sign of their friend. Had Joe been killed by the fall, or was he only stunned and unconscious? A great dread tugged at their hearts as they realized how little chance any one could have of surviving such a fall.
“Poor Joe!” whispered Herb. “What shall we do, Bob?”
“Go after him, of course,” was the decisive reply. “And we’ve got to go fast, because that TNT isn’t going to wait a minute for us.”
Mr. Mayhew overheard the boys as he and others of the crew approached the edge of the cleft, and he glanced at his watch.