"Stop! Stop, or we'll shoot!"
Matt and Chub stole a quick look behind. Two horsemen were in the road, and one of them was armed with a rifle.
"Faster!" cried Matt. "Get around the next turn!"
There was no need of a spur for Chub. His idea that the writer of that second note was "four-flushing" had proved to be a dream, and he was coaxing his motor-cycle to the limit.
Bang!
The sharp report echoed and reechoed through the hills, and a spurt of dust shot up between the two racing wheels.
"They're shooting at our tires!" called Matt.
"If they'll give us about a minute more," answered Chub, doubled over his handle-bars, "they can blaze away all they please. They've got to haul up if they do any straight shooting, and while they're standing still we're getting into the distance. If—— Wow!"
Chub broke off with a startled yell. One of the bullets had passed altogether too close to him for any sort of comfort.
The next moment the shoulder of a hill intervened between the boys and the marksman. They were safe for the moment, but, above the noise of their machines, they could hear a flurry of pounding hoofs.