“Ah, you are asking what has been puzzling me,” replied the doctor, “and I seem to be faced by a blank wall built-up between now and the past. If we could find anything in the shape of weapons or household implements, one might make a guess; but every trace we have found is of the last inhabitants.”
“Well, that ought to do,” said Chris.
“But I mean the pumas or jaguars that seem to have here and there turned the cells into caves, and left their gnawed bones about. They may have lived here fifty years ago, a hundred years, or five. But there is one thing evident, and it is this—that the people who lived here chose the place as being one that they could make into a stronghold, one which they could fortify so as to defend themselves from their enemies.”
“What enemies, sir?” asked Ned sharply.
“Ah, that I can’t tell you. The people here must have been to a great extent civilised, or they would not have been builders; and most likely their enemies were wild Indian-like tribes who roamed the plains, as they do to this day. I want to find something left by these builders, and then perhaps we might learn something.”
They had now come to the last of the long range of cells that they had been making their way through, and further progress was checked by solid rock which had evidently been neither chipped away nor added to.
They cautiously stepped through the front opening, to stand upon the rough, crumbled-away terrace, from which they could look down into the great depression where the ponies and mules were contentedly grazing, and for about the tenth time looked upward for some means of reaching the terrace above, one which appeared more time-worn and dangerous than that upon which they stood; but without ladders it would have been risking life to make any attempt to reach it.
“Strikes me, sir,” said Griggs, “that we’ve left the way up far behind.”
“Why?” said Wilton sharply.
“Because we’ve seen no way here, and we found one there.”