Overholt sat still, and saw, and wondered, and little by little the wheel and the soft vision of near happiness hypnotised him, for his body and brain were weary beyond words to tell, so that all at once his eyes were shut and he was sleeping like a child, as happy in dreamland as he had just been awake; and happier far, for there was a dear presence with him now, a hand he loved lay quietly in his, and he heard a sweet low voice that was far away.

The boy saw, and understood, for ever since he had been very small he had been taught that he must not wake his father, who slept badly at all times, and little or not at all when he was anxious.  So Newton would not disturb him now, and at once formed a brave resolution to sit bolt upright all night, if necessary, for fear of making any noise.  Besides, he did not feel at all sleepy.  There was the Motor to look at, and there was Christmas to think of, and it was bright and clear outside where the snow was like silver, under the young moon.  He could look out of the window as he sat, or at his father, or at the beautiful moving engine, or at the little City of Hope, all without doing more than just turning his head.

To tell the truth, it was not really a great sacrifice he was making, for if there is anything that strikes a boy of thirteen as more wildly exciting than anything else in the world, it is to sit up all night instead of going to bed like a Christian child; moreover, the workshop was warm, and his own room would be freezing cold, and he was so well used to the vile odour of the chemical stuff, that he did not notice it at all.  It was even said to be healthy to breathe the fumes of it, as the air of a tannery is good for the lungs, or even London coal smoke.

But it is one thing to resolve to keep awake, even with many delightful things to think about; it is quite another to keep one’s eyes open when they are quite sure that they ought to be shut, and that you ought to be tucked up in bed.  The boy found it so, and in less than half an hour his arm had got across the back of the chair, his cheek was resting on it quite comfortably, and he was in dreamland with his father, and quite as perfectly happy.

So the two slept in their chairs under the big bright lamps; and while they rested the Air-Motor worked silently, hour after hour, and the heavy wheel whirled steadily on its axle, and only its soft and drowsy humming was heard in the still air.

That was the most refreshing sleep Overholt remembered for a long time.  When he stirred at last and opened his eyes, he did not even know that he had slept, and forgot that he had closed his eyes when he saw the engine moving.  He thought it was still nine o’clock in the evening, and that the boy might as well finish his little nap where he was, before going to bed.  Newton might sleep till ten o’clock if he liked.

The lamps burned steadily, for they held enough oil to last sixteen hours when the winter darkness is longest, and they had not been lighted till after supper.