be worth—why, Tom, it's imposible. It would be worth millions—all the wealth of a world must be in the underground city. It's impossible Tom, my boy!"
"Well, that may be," agreed Tom. "I'm not laying it's true. Mr. Illingway is telling only what he heard."
"Go on! Tell some more." begged Mr. Damon. "Bless my shirt studs, this is getting exciting!"
"He says that the traveler told of this underground city of gold," went on Tom, "though he had never been there himself. He had met a native who had located it, and who had brought out some of the gold, including several of the images. and one he gave to the white man in return for some favor. The white man took it to Africa with him."
"But where is this underground city, Tom?" asked Mr. Swift. "Doesn't Mr. Illingway give you any idea of its location."
"He says it is somewhere in Mexico," explained the lad. "The Africans haven't a very good idea of geography, but some of the tribesmen whom the white traveler taught, could draw rude maps, and Mr. Illingway had a native sketch one for him, showing as nearly as possible where the city of gold is located."
"Tom Swift, have you got that map?" sud-
