“Oh, he’s getting along,” replied Dr. Sherwood to Tom’s question. “That is, physically. His leg has mended, though he still has to use a cane. But his head isn’t clear yet. He can’t talk intelligently. As a matter of fact, perhaps he never will.”

“You don’t mean that he may be insane for the rest of his life!” exclaimed Tom, genuinely shocked.

“That’s among the possibilities,” affirmed the doctor. “Though considering his youth and vitality—he’s a strong young fellow—the chances are that he’ll recover. Still, no one can tell. You can go out and take a look at him yourself if you like. He’s sunning himself on a bench in the garden.”

Tom went out and seated himself on the bench beside the invalid. He had a good look at him for the first time under anything like normal conditions. The young aviator had evidently been sinewy and stalwart when in health, judging from his frame, though now thin from his long illness. His face must have been a pleasant one, though marred now by the vacant look in his eyes.

Tom tried to get in conversation with him.

“How are you, Hillobie?” he asked, using the name at a venture.

The boy looked at him without any sign of interest and made no reply. Tom tried again several times but fruitlessly, and at last had to give it up. He left the hospital in a depressed mood, wondering if, after all, he had done the young man a real service in saving his life. Of what use was life without reason?

The Swift Construction Company hurried things along, and in about a week Tom was ready for the start. The young inventor had decided to take Koku with him, as his great strength and loyal devotion might prove invaluable. The giant was in great glee and grinned from ear to ear when apprised of Tom’s decision, but Rad was thoroughly disgusted.

“To hev dat big chunk o’ beef clutterin’ up the plane!” he snorted. “Doan know whut you must be t’inkin’ uv, Marse Tom.”

“But don’t you see, Rad,” said Tom soothingly, trying to keep a serious face, “that I wouldn’t dare go off and leave this place alone without you to take care of things? How could I have an easy minute unless I could keep saying to myself: ‘Everything’s all right at home. Rad’s on the job?’ ”