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:
