“Matter?  What do you mean?”

“I mean what made you make up your mind so quickly to go on this expedition when you heard Beecher was going?”

“Oh—­er—­well, you wouldn’t want to see our old friend Professor Bumper left, would you, after he had worked out the secret of the idol of gold?  You wouldn’t want some young whipper-snapper to beat him in the race, would you, Ned?”

“No, of course not.”

“Neither would I. That’s why I changed my mind.  This Beecher isn’t going to get that idol if I can stop him!”

“You seem rather bitter against him.”

“Bitter?  Oh, not at all.  I simply don’t want to see my friends disappointed.”

“Then Beecher isn’t a friend of yours?”

“Oh, I’ve met him, that is all,” and Tom tried to speak indifferently.

“Humph!” mused Ned, “there’s more here than I dreamed of.  I’m going to get at the bottom of it.”

But though Ned tried to pump Tom, he was not successful.  The young inventor admitted knowing the youthful scientist, but that was all, Tom reiterating his determination not to let Professor Bumper be beaten in the race for the idol of gold.

“Let me see,” mused Ned, as he went home that evening.  “Tom did not change his mind until he heard Beecher’s name mentioned.  Now this shows that Beecher had something to do with it.  The only reason Tom doesn’t want Beecher to get this idol or find the buried city is because Professor Bumper is after it.  And yet the professor is not an old or close friend of Tom’s.  They met only when Tom went to dig his big tunnel.  There must be some other reason.”

Ned did some more thinking.  Then he clapped his hands together, and a smile spread over his face.

“I believe I have it!” he cried.  “The little green god as compared to the idol of gold!  That’s it.  I’m going to make a call on my way home.”

This he did, stopping at the home of Mary Nestor, a pretty girl, who, rumor had it, was tacitly engaged to Tom.  Mary was not at home, but Mr. Nestor was, and for Ned’s purpose this answered.

“Well, well, glad to see you!” exclaimed Mary’s father.  “Isn’t Tom with you?” he asked a moment later, seeing that Ned was alone.

“No, Tom isn’t with me this evening,” Ned answered.  “The fact is, he’s getting ready to go off on another expedition, and I’m going with him.”

“You young men are always going somewhere,” remarked Mrs. Nestor.  “Where is it to this time?”

“Some place in Central America,” Ned answered, not wishing to be too particular.  He was wondering how he could find out what he wanted to know, when Mary’s mother unexpectedly gave him just the information he was after.

“Central America!” she exclaimed.  “Why, Father,” and she looked at her husband, “that’s where Professor Beecher is going, isn’t it?”

“Yes, I believe he did mention something about that.”