Chapter VI. "Beware the Head-Hunters!"

"That's what I want!" exclaimed the young inventor, as he finished the perusal of the missionary's missive.

"What is it?" asked Mr. Swift, entering the shop at that moment.

"News from Africa, dad. Mr. Illingway went to a lot of trouble to get more information for us about the city of gold, and he sends a better map. It seems there was one among the effects of the white man who died near where Mr. Illingway has his mission. With this map, and what additional information I have, we ought to locate the underground city. Look, dad," and the lad showed the map.

"Humph!" exclaimed Mr. Swift with a smile. "I don't call that a very clear map. It shows a part of Central Mexico, that's true, but it's on such a small scale I don't see how you're going to tell anything by it."

"But I have a description," explained Tom. "It seems according to Mr. Illingway's letter, that you have to go to the coast and strike into the interior until you are near the old city of Poltec. That used to be it's name, but Mr. Illingway says it may be abandoned now, or the name changed. But I guess we can find it."

"Then, according to what he could learn from the African natives, who talked with the white man, the best way is to hire ox carts and strike into the jungle. That's the only way to carry our baggage, and the dirigible balloon which I'm going to take along."

"Pretty uncertain way to look for a buried city of gold," commented Mr. Swift. "But I suppose even if you don't find it you'll have the fun of searching for it, Tom."

"But we are going to find it!" the lad declared. "We'll get there, you'll see!"

"But how are you going to know it when you see it?" asked his father. "If it's underground even a balloon won't help you much."

"It's true it is underground," agreed Tom, "but there must be an entrance to it somewhere, and I'm going to hunt for that entrance. Mr. Illingway writes that the city is a very old one, and was built underground by the priests of some people allied to the Aztecs. They wanted a refuge in times of war and they also hid their valuables there. They must have been rich to have so much gold, or else they didn't value it as we do."

"That might be so," assented Mr. Swift. "But I still maintain, Tom, that it's like looking for a needle in a haystack."

"Still, I'm going to have a try for it," asserted the lad. "If I can once locate the plain of the big temple I'll be near the entrance to the underground city."

"What is the 'plain of the big temple,' Tom?"

"Mr. Illingway writes," said the lad, again referring to the letter, "that somewhere near the beginning of the tunnel that leads into the city of