City reservoir they had succeeded where trained
men had failed; and they meant to succeed here also. They felt that
the Chief was patting them on the head, as it were, and telling them
that they were good little boys. They meant to show him they were the
equals of his own men, even if the Chief's words, instead of pleasing
them, stimulated them to half angry activity.

"He needn't think that just because we're boys and come from the
country we aren't any good," argued Roy. "That's the way everybody
talks about boys. That's the way they talked about us at Elk City
until we caught the dynamiters and showed them what we could do. We'll
show Uncle Sam's men, too. I don't care if they are famous detectives.
We'll get these fellows ourselves. We're not going to have the secret
service step in now and take all the credit."

But it was one thing to talk so confidently and quite another to
accomplish the end they were striving for. They had not yet discovered
a single one of the hidden wireless stations, and the secret of the
dollar was still a secret. As far as the members of the wireless
patrol could see, it was likely to remain a secret. How they could
secure one of the dollars without being detected, they did not know;
and how they were to read the message, even if they did get the dollar,
was more than they could see; for by this time they had dropped the
idea that the messages were engraved on the coins. More and more those
dollars appeared a great and insuperable obstacle.

"Couldn't we manage to see the spy when he marks those dollars?" asked
Roy. "Is there any way that we could get into his house and hide, so
as to watch him?"

"You mustn't think of trying," said Captain Hardy decisively. "But
possibly you could find a new place to watch from that would enable you
to see him better. These field-glasses of mine are very powerful, and
if you can find the proper view-point, you can see him well, even from
a distance."

Without a word Roy grabbed his hat and darted out of the house. A
second later he was slipping through the thicket on the sloping
hillside. Cautiously he crawled from one point to another. The only
station that gave any promise of success was the pine grove originally
selected. The tree from which they had been watching the spy's house
was a giant pine that towered above every other tree in the grove. But
the scouts had never dared to ascend beyond the protecting foliage of
the other