"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 helplessly. "By the bucking bulls of
Bedlam, this is a nice mess."

"Maybe we could throw rocks at him and chase him away," suggested Tom.

"No chance; he's got his eye on the professor," returned Jack, "and if
we did get out he would chase us and that wouldn't do the professor
any good."

"Can't you help me, boys," inquired the professor in an agonized tone.
"This tree limb is not exactly--er--comfortable."