“Let’s go over there and see at once,” said Dick.  “Frantic frogs of France, if the professor’s tumbled into a well he may be in serious trouble.”

They set off on the run to where a pile of stones showed a well-curb had once been.  The hoards at the top, which had covered it over, had rotted, and there was a jagged hole in them.  Jack cautiously bent over and placed his mouth at the edge of the hole.

“Professor, are you down there?” he hailed.

“Y-y-y-y-yes,” came up in feeble, stuttering tones.  “I’m almost frozen.  I’m hanging above the water but I can’t hold on much longer.  The bag of specimens is too heavy.”

“Throw it away,” urged Jack.

“N-n-n-not for worlds,” was the reply.  “I was looking for another rare bit of quartz when I fell in here.”

“I’ll run to the car,” said Jack, who had made out that the well was not very deep.  “Fortunately, we’ve got a rope and tackle in there.  Hold on, professor, we’ll soon have you out.”

He hurriedly explained the situation to the others and ran at top speed to the car, in which the boys—­like most careful motorists, who never know when such a piece of apparatus may come in useful for hauling a car out of mud or sand, for instance, or for towing an unlucky autoist home—­had a block and tackle stowed.

He was soon back, and the rope was lowered to the professor, who made it fast under his arms.  Then, aided by the husky muscles of the farm hands, they soon drew him to the surface.  But his weight was materially added to by the stones, and it was no light task to rescue him, dripping and shivering, from the dark, cold shaft.

He explained that soon after they had gone some men came up and drove the bull away.  But they had seen the gap in the stone wall first.

“They were positively violent,” declared the professor, “and said that they’d have the man who did it arrested if they could find him.  Under the circumstances, I deemed it prudent to stay up in the tree, where they could not see me.  They drove the bull off into another pasture.  As soon as the coast was clear I climbed down, but I happened to see a rare bit of quartz sparkling in the sun on the edge of the well-curb.  Imprudently I stood on the planking and fell in.”

“Gracious, it’s a lucky thing you weren’t drowned, with all that weight round your neck,” declared Jack.

“It was fortunate,” said the scientist mildly, as if such a thing as drowning was an everyday occurrence.  “As a matter of fact, if I hadn’t succeeded in grasping a projecting stone and held on, I might have gone down.  It was an—­er—­a most discomforting experience.”

“Well, of all things,” exclaimed the red-faced man, “to go trapesing round the country collecting rocks!”

“Not rocks, sir—­geological specimens,” rejoined the professor with immense dignity, “and—­great Huxley!  Under your foot, sir!  Under your foot!”