"Be on your guard, Dave!" sang out Roger. "Those rascals will play some trick on us, if they can."
"I'm on the watch!" answered Dave.
As they bowled along all kept their eyes on the alert, and it was well that they did so, for at a turn they suddenly came upon some broken bottles thrown down just where the machines had to pass. Dave gave a yell of warning, and turned off the power and applied the brakes just in time, and, as before, Roger had to turn into the bushes, to avoid striking the turnout ahead.
"They thought they'd make us cut our tires," said Dave.
"Right you are," answered Phil. "Phew! If we had gone over that glass we might have had some nasty punctures or blow-outs."
"They ought to be arrested for this!" said Sam, wrathfully. "It's against the law to put glass on a public highway."
"We can't prove they did it," answered Ben. "If we accused them, of course they would deny it. But it shows their meanness."
The boys got out and picked up some of the glass, and swept the rest aside as well as they could. Then the machines were started up once more, and soon they came in sight of the Hook Stock Farm, and Dave beckoned to a man who stood near the gateway.
"Have you lost one of your bulls?" he asked.
"We sure have!" answered the man, quickly. "What do you know about him?"