“Looks as if a dynamite explosion had knocked it all apart,” observed Ned.

“It certainly does,” agreed Mr. Damon.

“Maybe Cortez, or some of those early explorers, blew it up with gunpowder after fighting the Aztecs, or whatever the natives were called in those days,” suggested Tom.

“Bless my bookcase!  You don’t mean to say you think this temple goes back to those early days,” spoke Mr. Damon.

“Yes, and probably farther,” declared Tom.  “It must be very ancient, and the whole country about here is desolate.  Why, the way the woods have grown up everywhere but on this plain shows that it must be three or four hundred years ago.  There must have been a city around the temple, probably Poltec, and yet there isn’t a trace of it that we have seen as we came along.  Oh, yes, this is very ancient.”

“It will be jolly fun to explore it,” decided Ned.  “I wish it wasn’t so near night.”

“We can’t do much now,” decided Tom.  “It will be too dark, and I don’t altogether fancy going in those old ruins except by daylight.”

“Do you think any of those old Aztec priests, with their knifes of glass, will sacrifice you on a stone altar?” asked Ned, with a laugh.

“No, but there might be wild beasts in there,” went on the young inventor, “and I’m sure there are any number of bats.  There must be lots of nooks and corners in there where a whole army could hide.  It’s an immense place.”

The ruined temple certainly was large in extent, and in its glory must have been a wonderful place.  The balloon came nearer, and then Tom let it sink to rest on the sand not far from the ancient ruin.  Out he leaped, followed by his friends, and for a moment they stood in silent contemplation of the vast temple.  Then as the last rays of the setting sun turned the white stones to gold, Tom exclaimed: 

“A good omen!  I’m sure the city of gold must be near here, and in the morning we’ll begin our search for the secret tunnel that leads to it.”

“That’s the stuff!” cried Ned enthusiastically.

An instant later it seemed to get dark very suddenly, as it does in the tropics, and almost with the first shadows of night there came a strange sound from the ruined temple.

It was a low moaning, rumbling sound, like a mighty wind, afar off, and it sent a cold shiver down the spines of all in the little party.

“Good land a’ massy!  What am dat?” moaned Eradicate, as he darted back toward the balloon.

“Bless my looking glass!” cried Mr. Damon.

A second later the noise suddenly increased, and something black, accompanied by a noise of rapidly beating wings rushed from one of the immense doorways.

“Bats!” cried Tom.  “Thousands of bats!  I’m glad we didn’t go in after dark!” And bats they were, that had made the noise as they rushed out on their nightly flight.

“Ugh!” shuddered Mr. Damon.  “I detest the creatures!  Let’s get under cover.”