was a tree with low-hanging boughs. As the bull charged through the gap, right on his heels, the professor, still with his bag, slung by its leather strap across his shoulders, swung himself up into the lower limbs.
The boys set up a cheer.
"Good for you, professor!" cried Dick, as the bull, with lowered head and horns, charged into the tree and made it shake as if a storm had struck.
[Illustration: He was only in the nick of time.--_Page 22._]
"Wow! That's the time he got a headache!" cried Tom excitedly, as the professor, clinging desperately to his refuge, was almost flung from it by the shock.
"Gracious, boys, what shall I do?" he asked, looking about him from his leafy perch with a glance of despair that would have been comical had the situation not been serious, for the bull, instead of accepting his defeat, stood under the tree pawing and ramping ferociously.
"Well, here's a fine kettle of fish!" exclaimed Jack. "What are we going to do now?"
"Blessed if I know," said Dick helples