Though Tom received and wrote letters, the worried air did not depart from him and Ned knew his chum had a sore feeling in his heart. He was disappointed that Mary had not seen the new car before going away.
But if the young inventor was not privileged to listen to Mary's praise, he had the chance to hear the enthusiastic comments of Mr. Damon who came over a few days after his night break-down.
"Bless my safe deposit box, Tom!" exclaimed the eccentric man, "but I regard your House on Wheels as one of the most marvelous inventions of all time!"
"Strictly speaking it isn't an invention," said Tom. "It is merely an adaptation of several existing ones. I've simply taken a small house and put it on an automobile body."
"But you have done it very cleverly," said Mr. Damon. "This is an age of travel, Tom, and everybody is doing it. Now the one great drawback of travel is to find a place to stay at night, for no one likes to journey after dark, unless in a sleeping car.
"So it has come about that there are hotels and you know what a bother it is to arrange for a night's stay. But now you come along with a house in which a person can travel all day, as in an ordinary automobile. Then at night, when getting to a town, instead of having to hunt up a garage and then a hotel, you just pull your bed down from the wall and tumble in. It's great!"
"Well, I thought of that," Tom said. "I'm hoping it will be the success I think it may be."
"Of course it will be!" declared Mr. Damon. "You can book my order for one now, Tom."
"Consider it booked!" and the young inventor smiled for one of the few times since Mary had gone away.
In spite of the fact that the House on Wheels was, to the unobservant, well nigh complete the day Mary Nestor went away, Tom said considerable yet remained to be done, and for another week he and his men labored hard over the structure.