ebody else will have to do it now."

"You mean," said the Supervisor, flaming, "that those trees were
deliberately brought here to infect the forest, trees full of beetles?"

"Sure, 'tis as plain as the nose on your face," said McGinnis. "An' it's
dubs we were not to see it ourselves."

"And it was--?"

"The bucko pea-jammer that I gave a lickin' to in the spring, for sure,"
said McGinnis. "Peavey Jo, of course, who else?"

[Illustration: WILBUR'S OWN BRIDGE.

Light structure made by the boy over stream just below his camp.

_Photograph by U. S. Forest Service._]

[Illustration: WHERE THE SUPERVISOR STAYED.

The Ranger's cabin where the men gathered to fight the invasion of the
bark beetle.

_Photograph by U. S. Forest Service._]

CHAPTER X

A FOURTH OF JULY PERIL

Wilbur stayed but a few days at headquarters, the Supervisor and
Rifle-Eye having succeeded in trailing the wagon that had deposited the
trees from the point of its entrance into the forest to the place it
went out, by this means ensuring the discovery of all the spots where
diseased trees had been placed. One of them was in Wilbur's section of
the forest, and he was required to go weekly and examine all the trees
in the vicinity of the infected spot to make sure that the danger was
over. But, thanks to Rifle-Eye's discovery, the threatened pest was
speedily held down to narrow limits.

This added not a little to the lad's riding, for the place where Peavey
Jo had deposited the infected tree in his particular part of the forest
was a long way from the trail to the several lookout points to which he
went daily to watch for fires. Fortunately, having built the little
bridge across the canyon, and thus on one of the days of the week
having shortened his ride, he was able to use the rest of the day
looking after bark-beetles. But it made a very full week. He could not
neglect any part of these rides, for June was drawing to an end and
there had been no rain for weeks.

One night, returning from a hard day, on which he had not only ridden
his fire patrol, but had also spent a couple of hours rolling big rocks
into a creek to keep it from washing out a trail should a freshet come,
he found a large party of people at his camp. There was an ex-professor
of social science of the old regime, his wife and little daughter, a
guide, and a lavish outfit. Although the gate of Wilbur's corral was
padlocked and had "Property of the U. S. Forest