CHAPTER XIX.
WHAT WAS FOUND UNDERGROUND.
While Fremont was clambering down the eastern slope, studying the renegade Englishman whenever opportunity offered, and puzzling over the source of the fellow's information concerning the Cameron building and the Tolford estate papers, Ned Nestor and his companions were preparing to visit the interior of the strange shelter-place in which they found themselves.
The outer chamber, which, for convenience they marked "Chamber A" on the rough map they afterward made, was 30x40 feet in size, with the eastern side running parallel with the almost perpendicular face of rock which shot upward from the shelf which has before been alluded to.
The opening faced directly east, and from it one could look miles over the desert of sand lying between the foot of the range and the Rio Grande del Norte, something like a hundred miles away.
To the north and south of this main chamber the boys found niches in the rock, evidently hewn there by man hundreds of years before.

The rock was very hard here, and it seemed that work had ceased for that reason.
On the west side of the chamber there were two openings, perhaps four feet by six, each leading into a chamber 20x30 feet in size.

Before entering these rooms, which held an odor of dampness and decay, the recently arrived Black Bears produced electric flashlights.
"We looked up Old Mexico," Harry Stevens said, turning on the flame, "and knew we'd be nosing around in caves and tunnels before we got back to God's country, so we brought our glims along with us." "Well, don't burn them all at once," advised Nestor.

"We shall need them for several days, probably, and there are no shops in the next block where dry batteries can be bought.

Leave one out and put the rest away." "We have a few extra batteries," said Harry.