approval.

"Good for Phipps!" exclaimed Captain Crawford, at dinner. "Guess we can spare you chaps some service revolvers if you want 'em. How about it, Gerald?"

"Fine!" cried Jerry delightedly. "Sure we want 'em."

"We won't really need them, I s'pose?" asked Fred.

"You may," returned the captain. "Especially if you're going up against that sheep-destroyer of Phipps'. Looks to me like it was some cattle men from the ranges over beyond the Circle B. P. If it is you'll have to pass it up. If it's some animal or other, go to it!"

Herb and Gray arrived before the sunrise gun boomed next morning, and after a hasty breakfast the party rode to the northwest. They soon found themselves among the hills that bordered the river, and about ten o'clock Carlito halted them.

"See that cliff yonder?" Jerry pointed to a steep ascent that rose above the low water across the river. Halfway up could be seen a crumbling ruin from which rose a trail of smoke. "There's a cliff dwellin', Windy. Looks like old Tommy's home too."

"Tommy's the only Mojave there who can talk any English," explained Dunk as they splashed through the river. "We'll leave the horses down here an' hike up."

Leaving the ponies to graze along the river bank the boys began the ascent of a well-worn path. It had been hollowed out in places and made easier for visitors, so that they had no difficulty in reaching the cliff dwellings on the ledge. As they did so, Fred, who had followed Carlito closely, saw two wrinkled and blanket-clad Indians with a couple of fat squaws, seated over a small fire. One of the chiefs was hideously tattooed on the forehead and chin, and the women were heavily ornamented with strings of many-colored beads and gaudy pendants. Two of them wore large brass earrings. All had a miscellaneous supply of brass buttons distributed over their blankets.

"Hello, Tommy!" called Jerry cheerfully as he gained the ledge. "Better bring over some more stuff! We've got some new people at the post. Sell some baskets easy."

The eldest Mojave shook his head without looking up. "No tadavia," he returned. "No got. Nex' week, mebbe. All gone."

"You fellows show Windy over the place," said Carl. "I'm going to talk to Tommy." Squatting down beside the other Indians, he broke into a flood of Mexican.

"Come on, Windy," laughed Dunk. "Carl ain't got no use for us now."

At first Fred was somewhat disappointed in the cliff dwellings, or what was left of them. Only part of the walls were standing in many cases, the roofs having caved in, the remainder of the buildings being surrounded by fallen rocks and mortar.

"I suppose these are a good many hundred years old," he said as he stepped into one of the better preserved caves which the Indians had taken possession of. There was a rounded hole in the center of the stone floor where the inhabitants had ground their corn, and this was still in use by Tommy and his friends. All the arrow heads and broken pottery had been taken away by previous visitors, but the walls were inscribed with strange characters, the sign language of the vanished race. Queer animals of all sorts drawn in crude fashion, mingled with figures of dogs, snakes and mysterious marks of their own, were among the rough drawings.

Very little light came in through the narrow door and single small window, and when Fred emerged and stood at the edge of the terrace the bright sunshine made him blink his eyes, and the fresh beauties of nature were a strange contrast to the dark, dusty interior of the cliff house. They were now far above the river, which could be heard below. Opposite was a low hill or two and beyond the hills the blistering yellow and red of the desert. They were facing the garrison, which was hidden by the hills. Behind them lay the mountains, and to the west a far-off snowy peak was just visible around the corner of the ledge.

"She's fifty miles away," said Herb, as he pointed to the latter. "Looks about ten, eh? Seems like yuh could toss a stone into them hills yonder."

Fred had not yet become used to judging distances in this country, where the atmosphere was wonderfully clear. It seemed almost incredible to him that the mountain was so far away. He would have liked more time to explore other of the cliff dwellings, for the strange sights held his interest, but the other boys, who had been over the ground many times, seemed to be growing impatient, and they all returned to where Carl was still talking to Tommy. They stood behind the silently working Indians, whose faces were as expressionless and inhospitable as their bent backs.

"Just see 'em weave," exclaimed Fred, as the large but deft fingers wound in and out through many colors of straw.

"And listen to Carl and that Indian jabber," he continued. "I didn't know they could talk so fast."

"Oh, the Indians around here are partly civilized," said Jerry, who had been watching with them. "As long as they can get good trade for their baskets and beadwork, and do some swapping now and then, they seem satisfied."

Carl finally ended his conversation with Tommy, and springing to his feet, in true Indian fashion, he joined the other boys and sat down to eat the lunch which they had brought with them. After Fred had induced Tommy to part with a beaded buckskin knife sheath for a dollar, all returned down the winding path to the river.

"Well, I've got some red-hot news for you," announced Carlito, as they left the river behind and headed back through the low hills toward the fort.

"Yuh must 'a' got it from Tommy, then," returned Herb. "Yuh ain't done nothin' but jabber Greaser to him and old Alche-say. What's on your mind?"

"Why, Tommy's the oldest buck anywhere around here," replied Carlito. "I thought maybe he'd give me some dope on the Thunder Bird. I don't know anything but what I heard when I was a little kid, but I got him to loosen up. Want to hear it?"

"Sure," cried Dunk, and drew back his pony beside Carl. "Come on back here, Windy! Slow down, Jerry. Now we're fixed."

"What I told you before," began Carlito when all were riding in a bunch around him, "was true enough. Deputies from the tribes met twice a year, spring and fall. This was all long before the white men ever showed up. Tommy says—and he ought to know if anyone does—that somewhere up in the mountains north of here was the shrine of the Thunder Bird. It seems that there were three medicine men who kept an altar for offering sacrifices to the Thunder Bird three times a year, and there were great festivities in which the people took part. One year there was a big scrap on between the Navajos and some of my own people. While the deputies were worshipping at the altar that fall, somebody said something, and the Apache delegates pulled out hidden knives and killed a Navajo. It was a rule that no weapons were allowed on the sacred place, and no sooner had the blood been shed than the Thunder Bird came down in a big-storm and killed the whole bunch with his lightning arrows."

"And that's the kind of a monster we have to fight!" exclaimed Fred.

"Oh, well, that's the way Tommy told it. I suppose they really got struck by lightning. Anyhow, everyone was killed, even the medicine men, except one brave who crawled away with the news and died. It was a sacred law that no one could visit the shrine in the daytime except during the sacrifices. Everybody was scared to go after the bodies until next spring. Then some medicine men tried it. They got about halfway when the Thunder Bird flew down in the dark and beat them off the path. After that it was said that the Thunder Bird was angry; so the sacred spot was left alone and gradually forgotten. Each tribe of Indians worshipped him at home, and the old custom was passed up. Tommy says that nobody knows now even where the sacred spot is. When he was a boy an old man told him it was on a high peak in the mountains, but hidden by some rocks and boulders so nobody could find it. It's all a legend now."

"That's funny," exclaimed