Besides, we are out of their latitude.

An ancient race of people--very ancient indeed lived in this canyon.

How long ago, it is impossible to tell." "They must have been birds," said the practical Jones.

"Now, how'd that tomb ever get there?
Look at it, will you ?" As near as we could ascertain, it was three hundred feet from the ground below, five hundred from the rim wall above, and could not possibly have been approached from the top.

Moreover, the cliff wall was as smooth as a wall of human make.
"There's another one," called out Jones.
"Yes, and I see another; no doubt there are many of them," replied Wallace.