“That, for a beginning, isn’t so bad, Mr. Curley,” he said, as the gentleman was shaking hands cordially with him. “I’m meaning to use every cent of this money to advance several little schemes I’ve got started. Only for my need of cash to push them along mebbe you mightn’t have got that stabilizer without a few bids from other companies; but you sure treated me white, Mr. Curley, and I wanted you to know I appreciate it.”

Possibly Mr. Curley may have thought that Hiram had worked a pretty sharp trick on them in hanging around, and learning what they thought about his invention before disclosing his identity; but then certain things are allowable in business, and at least he had shown himself capable of looking after his own interests.

“If any of your later ideas happen to be in line with our work, Mr. Nelson,” the head of the firm said, “I hope you will give us a look at them before you approach any rival company. In one way it is a good thing for an inventor to keep advancing with the firm who first patronized him, of course, granting that they will meet any price he may be offered elsewhere.”

“I guess I c’n promise you that, sir,” said Hiram, who was very happy, and at that moment felt drawn toward the fine-looking gentleman who had treated him so splendidly.

So the four boys wended their way toward the gates of the Exposition. Hiram hardly knew whether he was walking on air or on ground. It seemed to him that his heels must be made of some magical rubber that kept pace with his ecstasy of mind, for he came near dancing at times, much to the amusement of Rob.

“First thing for me to do, fellows,” Hiram said, as they reached the hotel, “is to send a night letter to my folks telling ’em that I’ve got the coin. My maw she believed in me right along, but dad he’s allers been kinder skeptical, you know, and used to say I was spendin’ heaps of money on foolishness. Guess he’s due to change his tune after this, hey?”

Rob found that there had been a telegram for him that morning which somehow he had failed to receive before leaving for the Exposition grounds. It was a night letter from Professor McEwen in answer to the one he had sent, signed by the name of Professor Marsh, who was in charge of the exhibit.

In this communication, limited to fifty words, the Edinburgh scientist tried to express the deep satisfaction he felt because Rob and Andy had successfully filled his place, and handed over that precious packet to the gentleman in charge, without any accident. He declared that he would remain until their return home, and that he hoped to be able to thank them again most heartily.

The boys were a happy lot that evening. They attended a theater where there was an instructive show well worth seeing by all scouts. Indeed, Hiram seemed to have actually grown two inches since morning.

Of course his chums gloried in his success; so that the rest of their stay at the City of the Great Exposition was likely to be one long picnic, with not a single hovering cloud to mar their pleasure.