ts of Diamond X ranch,
though at another point the holdings of Bud's father extended well to
the summit of one of the mountains.

Urging on their horses by heels and voices, the little party swept into
the glade, following a path, or "trail," as it should be called. This
trail had been worn by countless cattle going to the river to drink,
and the feet of the ponies now clattered along it.

A moment later, swinging around a little clump of trees, greasewoods
and sagebush, Bud and his cousins saw a sight which thrilled them
through and though, though perhaps Bud was more accustomed to such
stirring scenes than were the city lads.

In the midst of an encampment of tents, several men were kneeling down,
using packs and baggage as a barricade. They were firing over this
line of defense at objects unseen, but which, as the white puffs of
smoke showed every now and then, were easily guessed to be humans, with
more or less sinister motives.

There was a regular fusillade, as the party of cowboys approached, and
in addition a series of sharp and wild yells which, now that the scene
was reached, could be heard as arising from the underbrush outside the
camp.

The attackers of Professor Wright, for he later proved to be the owner
of the camp, were using their voices as well as their weapons to
intimidate the defenders.

"Greasers and some Indians!" cried Slim, as he swept on along the
trail. "Come on, boys!" he yelled and instantly his gun was in action,
as was that of Babe Milton.

"Oh, why didn't I bring mine?" mourned Bud.

"Tough luck!" exclaimed Nort.

The advent of the rescue party had an instant effect. No sooner had
Slim and Babe begun firing than there was silence on the part of the
attackers. A few scattering shots were fired, one or two more wild
yells smote the air and then there was more silence.

"That settles 'em," grimly observed Slim, as he began to reload his
weapon, an example followed by Babe. At the same time those in the
little camp, who had had their backs turned toward the rescue party,
swung about with evident signs of relief on their faces.

A tall, slim man, with prematurely gray hair, stepped forward, resting
the butt of his rifle on the ground as he surveyed the newcomers. Then
his eyes sought those of Professor Blair.

"I see that you found help," he remarked quietly. "And just in time,
too. They were about to rush us, I fear."

"I'm glad we came in time," the other scientist