out of the defile.

"Well, I reckon we're all ready," observed Old Billee on a certain
morning a few days after the first failure. "How about it, Bud?"

"All set," answered the ranch owner's son, for he had recovered from
the gas he had inhaled and was quite fit again. "Let's go!" he cried.

The cavalcade moved forward, and when within about the same distance as
before from the defile, the horses were led aside, the guard posted and
the men again advanced up the gorge.

"Don't make any more noise than you can help," warned Bud, as one of
the men rattled some of the loose stones.

"Oh, I think they know we're coming," said Dick.

"You do? How?"

"Well, naturally they have scouts posted. We'd do the same if we were
in their position. They know we're coming, all right."

"Perhaps so," Bud admitted. "Well, everybody have his mask ready to
slip on as soon as gas is smelled."

"What if they use a kind we can't smell until it's too late?" asked
Dick.

"Well, that's a chance we have to take," said Bud with a shrug of his
shoulders.

"I think I shall smell it all right," Snake interjected. "I was pretty
good at that sort of thing in the war. The officers said I had a
mighty good nose--for smelling I mean," he made haste to add for fear
his pals would accuse him of personal vanity. "In some of the trenches
they used rats and canary birds to give warning of gas. But I was the
official smeller for my bunch, and I got so I was pretty good at it if
I do say it myself."

"Then we'll make you the advance guard," decided Bud, and so it was
arranged.

Up the gulch they marched, with guns and gas masks ready, and once
more, as on the former occasion, they were just within sight of the
cave when Snake cried:

"Gas! Gas!"

At once each man donned his protector, and then, looking like
prehistoric monsters the crowd, led by Bud, Nort, Dick and Old Billee
rushed to the attack. The same white wisps of vapor floated down into
the faces of the avengers, but there was no turning back now. There
was no choking or gasping. The gas masks were a perfect protection.

Dick's surmise that the advancing party was being spied on seemed to be
correct, since before they reached the cave shots came from the cavern,
and there was the vicious whine and ping of bullets. One or two of the
cowboys were hit, one seriously, and then the avengers began shooting
on their own account.

Bud gave the signal for a rush attack and eage