"No one knows," was the truthful and unhesitating reply. "It is a puzzle that so far archæologists have tried in vain to solve. They must be older than the Aztlan civilizations——"
"What are those?" asked Phil.
"Aztecs, Toltecs, and that bunch, aren't they?" queried Roger, wanting to show his knowledge.
"Mayas, too," said the other, smiling assent, "and they must be older than the Nahoa empire, of which little is left except in the south of Peru. Just how old is impossible to say, and the only clew we have is that these canals and ditches are in part filled up with volcanic lava and debris from the Bradshaw mountains, and geologists are able to show that these eruptions cannot have taken place less than two thousand years ago."
"That's as old as Rome!" said Roger in surprise.
"That means that the end of it, at latest guess, was older than the beginning of Rome, practically. And, though this volcanic action has been later than these immense works of early man in America, there is left neither a tradition of the millions of people who lived then, nor even of the forces which led to the decay of the empire and the overwhelming volcanic disaster in which it may have closed."
On their way back to the train, the old traveler gave Roger a long account of the early settlement of that part of the country by the Spaniards, and pointed out, as they passed through Tucson a few hours later, the quaint mediæval architecture of a town which claims its beginning as far back as 1560, and in which many houses three centuries old are still standing; the oldest town in the Southwest, with the exception of Santa Fé.
A mirage, or rather a succession of them, formed the basis for some thrilling African desert tales, with which Phil's father was well-primed, and when, passing round the mile-long horseshoe curve, the train pulled into El Paso, Roger was extremely sorry to leave the friends who had made his trip such a pleasant one.
A few hours sufficed for the boy to purchase some trifles needed to make up his equipment, and bright and early the following morning he started for Aragon, where he would find out the location of the party he was to join. It was quite dull after the jollity and interest of the trip to El Paso, and Roger began to wish that he had arrived, and was pining to get into action again. But the incident for which he was anxious did not fail him. As the train pulled up at Chispa, a station about fifty miles west of Aragon, it was seen that almost the whole population of the village was at the depot, a crowd numbering perhaps twenty people, and foremost among them a man carrying a little girl, about eight years old, in his arms.
In answer to questions put to him in Spanish, for he could speak no English, the father explained his trouble by pointing to six little marks on the girl's leg, three groups of two, all near each other. No sooner was it seen what the trouble was than a big six-footer shouldered his way through the car.