worrying her mother by asking if she had got home, he thought.

"You're sure she went home?" his eyes dwelt rather sharply upon Bill's
lean, leathery face. Bill looked up from the slow disintegration of the
splinter. He spat toward the stove again, looked down at the splinter,
and then got up quite unexpectedly.

"Hell, no! I ain't shore, but I can quick enough find out." He brushed
past Sudden and took long steps toward the camp. Sudden followed him.

The boys were standing in a group, holding their hat brims down to shield
their eyes from the bitter glare of the sun while they gazed up into the
sky, their faces turned towards the south. A speck was scudding across
the blue--a speck that rapidly grew larger, circled downward in a great,
easy spiral. Sudden and Bill perforce turned and held their own hat brims
while they looked.

"Sa-ay, if that there's Skyrider sailin' around in an airship, he's shore
got the laugh on us fellers," Aleck observed, squinting his nose until
his gums showed red above his teeth. "Look at 'im come down, would yuh!"

"Wonder where he got it?" little Curley hazarded. "I always told you
fellers--"

"Does anybody know where Mary V went?" Sudden's voice brought them all
facing him. They looked at him uncomprehendingly for a minute, then
uncertainly at one another.

"Why--she was going to take a picture of a cactus. I dunno where she went
after that." This was Bud, a shade of uneasiness creeping into his face.

"Which way did she go? Toward home?"

"She started that way--back toward Snake Ridge--"

"I seen her riding east," Curley broke in. "Jake shore was pickin' 'em up
and layin' 'em down too. I thought at first he was running off with her,
but he wasn't. He slowed down, climbin' that lava slope--and after that
I didn't see no more of 'er."

Sudden looked at his watch, frowning a little. Mary V probably was all
right; there was nothing unusual in her absence. But this country south
of Snake Ridge was closer to the lawless land across the boundary than he
liked. Their very errand down there gave proof enough of its character.
North of Snake Ridge, Sudden would merely have stored away a lecture for
Mary V. Down here at Sinkhole--

"You boys get out and hunt her up!" he snapped, almost as though they
were to blame for her absence. "I didn't tell you before, but I'm telling
you now that rustlers have been at work down here, and that's why we're
taking the horses off this range. This is