The other was singular in the extreme. It was nothing less than that of a ruined fort, at no great distance from the place where the balloon was anchored, but high up on the side of a hill and surrounded by a clump of trees.
The fort was built of stone, and still of considerable strength, and so constructed that it could be defended, if occasion demanded, by two resolute young men against four score savages.
Duncan thought it somewhat strange, that there was no footpath leading towards it, and that it seemed to be avoided by the natives.
They found out afterwards that the place had been the scene of a cruel massacre of white men--Portuguese without a doubt--and that it was now supposed to be the abode of evil spirits.
All the better for our young adventurers. And they made up their minds to take possession of the old fort the very next day.
That afternoon, however, they removed everything from the car of the balloon, and camped just a little way therefrom.
They had lit a fire really more for the sake of light than heat, and for, many hours after the sun's last glow tipped the snowy summits of the mountains with pink and blue, and the stars had come out, they sat here talking of home. But not of home only, but of their future prospects.
"From several strange cavities I have observed in my rambles to-day," said Duncan, "I have come to the conclusion that the white men who built that fort were also miners. Everything points to this fact, and also, alas! to that of their murderous extermination by fire and by the spears of these fiendish savages."
"Yes, Conal, it may have been many long years ago, centuries perhaps, but who can say what discoveries we may not make next. There may be buried treasure!"
Both Conal and Frank opened their eyes wider now.