“Well, Jack,” he said to his son, when they had been left in sole possession of the Jarley mansion, “you and I must entertain each other this afternoon.  What shall we do?”

“I’d like to play choo-choo car with you,” said Jack.  “I’ll be the engine and you be the train.”

“Very well,” said Jarley.  “Have you got your steam up?”

“Yeth,” lisped Jack.  “All aboard!”

Jarley hitched himself on to the engine as best he could by grabbing hold of Jack’s little coat tail, and the train started.  It was the most tedious journey Jarley ever undertook.  The train went up and down stairs, out upon the piazza, and finally landed in the kitchen, where the engine fired up on such fuel as gingerbread and cookies.  Incidentally the train, as represented by Jarley, took on a load of freight, consisting of the same fuel, and off they started again.  At the end of a half-hour’s run Jarley was worn out, but the engine seemed to gather strength and speed the farther it travelled; and as it let out a fearful shriek—­possibly a whistle—­every time the rear end of the train suggested side-tracking and a cessation of traffic for a month or two, Jarley in his indulgence invariably withdrew the proposition.  The consequence was that when Mrs. Jarley returned from church Jarley was a wreck, and as he handed the engine over to the maternal care he observed with some testiness that in a well-kept household it seemed to him matters should be so arranged that a busy man should not be compelled to turn himself into a child’s nurse, especially on the one day of the week which he could devote to rest and relaxation.  “If I had that boy’s energy,” he said to himself as he fled to his library, “what wonders I would accomplish!  What a shame it is, too, that the wasted energy of youth cannot be stored up in some way, so that when there comes the real need for it, it can be made available!”

This thought was the germ of his invention.  As he lay there in the library he thought over the possibilities of life if the nervous force of childhood, the misdirected energy of play-time, could only be put by and drawn upon later just as man puts by the money he does not need in the present for use in case of future rainy days.  Then, as the sun sank below the hills and the twilight hours with their inspiring softness came on, Jarley resolved that he was the man to whom had come the mission which should make of this ideal a reality.  Probably in the full glare of day he would not have undertaken it; but Jarley, in common with most men of dreamy nature, felt in the quiet dusk the power to do all things.  He had the poetic temperament which sometimes leads on to great things, and the man so gifted who does not feel himself capable, at that hour of the day of rest, of battering down Gibraltar or of upbuilding the whole human race, must account himself a failure.