ddenly the whistling stopped. Looking, he saw Gabe hurry over to the
old tree trunk. He seemed to thrust his hand in, and draw something
out. Fred, watching sharply, noticed that the boy was deeply interested
in what he had taken from the hollow trunk; and he could give a pretty
good guess as to what this must be.

But Fred did not move from his place of concealment. Lying snugly
hidden he saw Gabe replace the little package, after which he stepped
out into the trail, picked up the ragtime air just where he had dropped
it, and came walking smartly along, a satisfied grin on his face.

Waiting until he had passed out of sight around a bend in the path, and
his loud whistle began to grow fainter in the distance, Fred hurried
over to the big tree.

He had noted that particular crevice in the hollow trunk too well to
make any mistake now. A minute later and he had fished up a little
cardboard box, not over four inches in length, and secured with a
rubber band.

With trembling fingers Fred took this fastening away, and raised the
lid; just as Gabe had recently done, no doubt being consumed by a
desire to feast his eyes once more on the contents.

Fred gave a satisfied sigh. It was all right, and Bristles' reputation
had been cleared; for in that little cardboard box which Gabe Larkins
had secreted so carefully lay seven milk-white opals, doubtless of
considerable value.

CHAPTER XXI

A PLAN TO CATCH THE THIEF

"That settles it!"

Fred was saying these three words over several times to himself as he
stood and stared at the seven little opals. They had appeared rather
pretty when he looked at them in Miss Muster's best room, on the
occasion of his visit there in company with Bristles. They gave him a
shiver now; just because he knew that they had tempted weak Gabe
Larkins to commit a terrible wrong.

What had he better do about it?

Fred had, in fact, about made up his mind that there was only one
course open to him in case he found the opals. This was to go to Miss
Muster at once, and let her know what had come to pass.

She would be glad, for the sake of Bristles and his parents--yes, Fred
began to believe the old maid really had a heart of her own, and would
herself rejoice over the vindication of her nephew.

But should he take the opals along with him? He decided against this as
unwise. To fully prove his case, he should be able to catch Gabe in the
act of handling the precious stones, and with a