Ned Newton decided to keep to himself what he had heard at the Nestor home. Not for the world would he let Tom Swift know of the situation.  
"That is, I won't let him know that I know," said Ned to himself, "though he is probably as well aware of the situation as I am. But it sure is queer that this Professor Beecher should have taken such a fancy to Mary, and that her father should regard him so well. That is natural, I suppose. But I wonder how Mary herself feels about it. That is the part Tom would be most interested in.
 
"No wonder Tom wants to get ahead of this young college chap, who probably thinks he's the whole show. If he can find the buried city, and get the idol of gold, it would be a big feather in his cap.
 
"He'd have no end of honors heaped on him, and I suppose his hat wouldn't come within three sizes of fitting him. Then he'd stand in better than ever with Mr. Nestor. And, maybe, with Mary, too, though I think she is loyal to Tom. But one never can tell.
 
"However, I'm glad I know about it. I'll do all I can to help Tom, without letting him know that I know. And if I can do anything to help in finding that idol of gold for Professor Bumper, and, incidentally, Tom, I'll do it," and he spoke aloud in his enthusiasm.
 
Ned, who was walking along in the darkness, clapped his open hand down on Tom's magazine he was carrying home to read again, and the resultant noise was a sharp crack. As it sounded a figure jumped from behind a tree and called tensely:
 
"Hold on there!"
 
Ned stopped short, thinking he was to be the victim of a holdup, but his fears were allayed when he beheld one of the police force of Shopton confronting him.
 
"I heard what you said about gettin' the gold," went on the officer. "I was walkin' along and I heard you talkin'. Where's your pal?"
 
"I haven't any, Mr. Newbold," answered Ned with a laugh, as he recognized the man.
 
"Oh, pshaw! It's Ned Newton!" exclaimed the disappointed officer. "I thought you was talkin' to a confederate about gold, and figured maybe you was goin' to rob the bank."
 
"No, nothing like that," answered Ned, still much amused. "I was talking to myself about a trip Tom Swift and I are going to take and——"
 
"Oh, that's all right," responded the policeman. "I can understand it, if it had anything to do with Tom. He's a great boy."
 
"Indeed he is," agreed Ned, making a mental resolve not to be so public with his thoughts in the future. He chatted for a moment with the officer, and then, bidding him good-night, walked on to his home, his mind in a whirl with conglomerate visions of buried cities, great grinning idols of gold, and rival professors seeking to be first at the goal.
 
The next few days were busy ones for Tom, Ned and, in fact, the whole Swift household. Tom and his father had several consultations and conducted several experiments in regard to the new stabilizer, the completion of which was so earnestly desired. Mr. Swift was sure he could carry the invention to a successful conclusion.
 
Ned was engaged in putting the financial affairs of the Swift Company in shape, so they would practically run themselves during his absence. Then, too, there was the packing of their baggage which must be seen to.
 
Of course, the main details of the trip were left to Professor Bumper, who knew just what to do. He had told Tom and Ned that all they and Mr. Damon would have to do would be to meet him at the pier in New York, where they would find all arrangements made.
 
One day, near the end of the week (the beginning of the next being set for the start) Eradicate came shuffling into the room where Tom was sorting out the possessions he desired to take with him, Ned assisting him in the task.
 
"Well, Rad, what is it?" asked Tom, with businesslike energy.
 
"I done heah, Massa Tom, dat yo' all's gwine off on a long trip once mo'. Am dat so?"
 
"Yes, that's so, Rad."
 
"Well, den, I'se come to ast yo' whut I'd bettah take wif me. Shall I took warm clothes or cool clothes?"
 
"Well, if you were going, Rad," answered Tom with a smile, "you'd need cool clothes, for we're going to a sort of jungle-land. But I'm sorry to say you're not going this trip."
 
"I—— I ain't gwine? Does yo' mean dat yo' all ain't gwine to take me, Massa Tom?"
 
"That's it, Rad. It isn't any trip for you."
 
"Is certain not!" broke in the voice of Koku, the giant, who entered with a big trunk Tom had sent him for. "Master want strong man like a bull. He take Koku!"
 
"Look heah!" spluttered Eradicate, and his eyes flashed. "Yo'—yo' giant yo'—yo' may be strong laik a bull, but ya' ain't got as much sense as mah mule, Boomerang! Massa Tom don't want no sich pusson wif him. He's gwine to take me."
 
"He take me!" cried Koku, and his voice was a roar while he beat on his mighty chest with his huge fists.
 
Tom, seeing that the dispute was likely to be bothersome, winked at Ned and began to speak.
 
"I don't believe you'd like it there, Rad—not where we're going. It's a bad country. Why the mosquitoes there bite holes in you—raise bumps on you as big as eggs."
 
"Oh, good land!" ejaculated the old colored man. "Am dat so Massa Tom?"
 
"It sure is. Then there's another kind of bug that burrows under your fingernails, and if you don't get 'em out, your fingers drop off."
 
"Oh, good land, Massa Tom! Am dat a fact?"
 
"It sure is. I don't want to see those things happen to you, Rad."
 
Slowly the old colored man shook his head.
 
"I don't mahse'f," he said. "I—— I guess I won't go."
 
Eradicate did not stop to ask how Tom and Ned proposed to combat these two species of insects.
 
But there remained Koku to dispose of, and he stood smiling broadly as Eradicate shuffled off.
 
"Me no 'fraid bugs," said the giant.
 
"No," said Tom, with a look at Ned, for he did not want to take the big man on the trip for various reasons. "No, maybe not, Koku. Your skin is pretty tough. But I understand there are deep pools of water in the land where we are going, and in them lives a fish that has a hide like an alligator and a jaw like a shark. If you fall in it's all up with you."
 
"Dat true, Master Tom?" and Koku's voice trembled.
 
"Well, I've never seen such a fish, I'm sure, but the natives tell about it."
 
Koku seemed to be considering the matter. Strange as it may seem, the giant, though afraid of nothing human and brave when it came to a hand-to-claw argument with a wild animal, had a very great fear of the water and the unseen life within it. Even a little fresh-water crab in a brook was enough to send him shrieking to shore. So when Tom told of this curious fish, which many natives of Central America firmly believe in, the giant took thought with himself. Finally, he gave a sigh and said:
 
"Me stay home and keep bad mans out of master's shop."
 
"Yes, I guess that's the best thing for you," assented Tom with an air of relief. He and Ned had talked the matter over, and they had agreed that the presence of such a big man as Koku, in an expedition going on a more or less secret mission, would attract too much attention.
 
"Well, I guess that clears matters up," said Tom, as he looked over a collection of rifles and small arms, to decide which to take. "We won't have them to worry about."
 
"No, only Professor Beecher," remarked Ned, with a sharp look at his chum.
 
"Oh, we'll dispose of him all right!" asserted Tom boldly. "He hasn't had any experience in business of this sort, and with what you and Professor Bumper and Mr. Damon know we ought to have little trouble in getting ahead of the young man."
 
"Not to speak of your own aid," added Ned.
 
"Oh, I'll do what I can, of course," said Tom, with an air of indifference. But Ned knew his chum would work ceaselessly to help get the idol of gold.
 
Tom gave no sign that there was any complication in his affair with Mary Nestor, and of course Ned did not tell anything of what he knew about it.
 
That night saw the preparations of Ned and Tom about completed. There were one or two matters yet to finish on Tom's part in relation to his business, but these offered no difficulties.
 
The two chums were in the Swift home, talking over the prospective trip, when Mrs. Baggert, answering a ring at the front door, announced that Mr. Damon was outside.
 
"Tell him to come in," ordered Tom.
 
"Bless my baggage check!" exclaimed the excitable man, as he shook hands with Tom and Ned and noted the packing evidences all about. "You're ready to go to the land of wonders."
 
"The land of wonders?" repeated Ned.
 
"Yes, that's what Professor Bumper calls the part of Honduras we're going to. And it must be wonderful, Tom. Think of whole cities, some of them containing idols and temples of gold, buried thirty and forty feet under the surface! Wonderful is hardly the name for it!"
 
"It'll be great!" cried Ned. "I suppose you're ready, Mr. Damon—you and the professor?"
 
"Yes. But, Tom, I have a bit of unpleasant news for you."
 
"Unpleasant news?"
 
"Yes. You know Professor Bumper spoke of a rival—a man named Beecher who is a member of the faculty of a new and wealthy college."
 
"I heard him speak of him—yes," and the way Tom said it no one would have suspected that he had any personal interest in the matter.
 
"He isn't going to give his secret away," thought Ned.
 
"Well, this Professor Beecher, you know," went on Mr. Damon, "also knows about the idol of gold, and is trying to get ahead of Professor Bumper in the search."
 
"He did say something of it, but nothing was certain," remarked Tom.
 
"But it is certain!" exclaimed Mr. Damon. "Bless my toothpick, it's altogether too certain!"
 
"How is that?" asked Tom. "Is Beecher certainly going to Honduras?"
 
"Yes, of course. But what is worse, he and his party will leave New York on the same steamer with us!"