“I would like to have two men volunteer to stay with me and the Radio Boys and try to rescue young Atwood,” he said. “The others will return immediately to the boat.”

Every member of the crew volunteered, and Mr. Mayhew selected two of the best men. Then he sent the rest back to the ship, and the little group of rescuers turned to their task with feverish energy.

“Some one will have to be lowered into the crevasse,” said the officer. “Who shall it be?”

Like a flash both Bob and Herb demanded the post of greatest danger. Bob was selected, as being the stronger. A rope was quickly made fast under his arms, and he was quickly lowered into the cold green depths of the iceberg.

Down, down he went, calling to his friend as he progressed. His own voice echoed and re-echoed in the depths, and once he was sure that he heard a faint cry far below him. After what seemed a long time, his feet struck a hard surface, and he found himself on a wide ledge that ran along the face of the ice wall.

He could see nothing of his friend, but this time, when he called out, he was certain that he heard Joe’s answering cry at no great distance. It seemed to come from the left, and Bob cautiously felt his way along the ledge, keeping as close to the wall as he could. He called again, and this time Joe’s voice was nearer. Keeping on, Bob rounded a slight projection and came face to face with his friend.

Joe was pale and shaken, but a great surge of relief went over Bob as he saw that his chum was on his feet, and apparently not badly hurt.

“Thank heaven I’ve found you, old fellow!” exclaimed Bob, a little brokenly. “How are you feeling?”

“A bit shaky, and weak in the knees, but I’ll get over that,” Joe replied, with an attempt at his old grin. “How are we going to get out of this?”

“I’ll tie this rope around you, and they can pull you up first. Then they can let it down again, and I’ll come up. We’ve got to work fast though,” and he looked significantly at his friend.