him. The man was good-natured, or perhaps
he rather liked the idea of a ride in such a novel-looking car.
Anyhow, he called three of his hands and told them to get pitchforks.

"Never see a bull I couldn't handle," he said as the men, having
returned, scrambled into the car.

"Do you know who it belongs to?" asked Jack, as he turned round and
headed back to where they left the luckless professor.

"I reckon it's that big Holstein of Josh Crabtree's. He's pretty near
as mean as his owner, and that's considerable."

Jack thought of the hole in the wall and hoped they would reach there
before farmer Crabtree, and so avoid serious complications.

He drove at top speed, while the friendly farmer and his workmen clung
to the sides of the car and looked rather scared at the rate they were
going.

"There's the tree," exclaimed Jack, as they came in sight of it, "and
there's the gap in the fence."

"And where's the bull?" asked Tom.

"And where's the professor?" added Dick.

Not a trace of the man of science or of the ferocious animal was to be
seen.

"Are you sure you boys didn't dream all this?" asked the red-faced
farmer suspiciously.

"There ain't even a cow in sight in the pasture lot," said one of the
men.

"I reckon this is some sort of a fool joke," added another.

"It isn't. Indeed, it isn't," protested Jack.

"The professor is some place around," said Tom.

But a lengthy search of the vicinity failed to show anything except
that the professor had vanished as if the earth had swallowed him.

CHAPTER IV.

"WHERE IS HE?"

"Professor!" hailed Dick, at the top of his lungs.

"Professor!" bawled the farm hands.

The red-faced farmer himself regarded the boys quizzically.

"What sort of a chap is this professor of yours?" he asked with an odd
intonation.

"He's a geologist," replied Dick. "Why?"

"Oh, I thought he might be a conjurer," was the rejoinder. "He seems
to be pretty good at hiding himself."

"Hark!" exclaimed Jack suddenly, standing at pause and listening
intently.

"What's up?" demanded Dick, instantly on the alert, too.

"I heard something. It sounded like----"

"There it is again," cried Tom.

A faint, far-off cry, impossible to locate, was borne to their ears.

"It's a call for help," declared Dick.

"That's what it is," agreed the red-faced farmer. "Must be that
perfusser of yours, but where in the name of Sam Hill is he?"

It was a puzzling question. The fain