Whack! clatter! plug! Four high school boys, all of them baseball
players and proud of their straight throwing, sent a small shower
of rocks whizzing through the air.

These struck the bridge planks well ahead of the horse.

"Stop---or the next ones will hit you!" shouted young Prescott.

Just by way of suggestion he threw one stone that flew by within
a foot of the nearer tramp's head. Holmes duplicated the throw.

"Stop that!" yelled one of the tramps, but he brought the horse
to a standstill.

"Don't you throw any more stones!" yelled the tramp, as he saw
the four ball players poised ready for more work in that line.

"Then hold the horse where he is until we come and take him,"
ordered Dick.

"We won't, and don't you throw any more stones," ordered the tramp.
"Jerry, turn your pistol loose on the young cubs if they throw
another stone. Giddap!"

"That's a bluff. You haven't any pistol," Dick called to the
tramps coolly. "Just start that horse, and we'll knock both your
heads off with stones. We know how to throw 'em."

Splash! Greg Holmes had taken to the narrow river. Now he was