letting us get by?" asked Jack.

The little man raised a hand protestingly.

"I'll be delighted to in just a moment," he said, "but just now it's
impossible. You see, I've just discovered a vein of what I believe to
be Laurentian granite running across the road. I am trying to trace it
and--what's that? Good gracious! Back up your machine, please. I
believe it runs under your wheel. I must make sure."

Jack obligingly threw in the reverse to humor the little man, who
darted forward and began scraping up the dust in the road with his
hands as if he had been a dog scratching out a rabbit hole. He began
chipping away eagerly with his hammer at some rock that cropped up out
of the road.

He broke off a piece with his hammer, which was an oddly shaped tool,
and drawing out a big magnifying glass scanned the chip intently. He
appeared to have forgotten all about the waiting boys. But now he
seemed to remember them. He looked up, beaming.

"A magnificent specimen. One of the finest I have ever seen. Most
remarkable!"

And with that he popped the bit of stone into his bag, which the boys
now saw was filled with similar objects.

"Maybe he'll let us get by now," remarked Tom, but a sudden
exclamation from Dick Donovan cut him short.

"Why, hullo, professor," he said, "out collecting specimens?"

The little man peered at him sharply. And then broke into a smile of
recognition.

"Why, it's Dick Donovan!" he beamed, hastening up to the car, "the
young journalist who wrote an article about my specimens once and
woefully mixed them up. However, to an unscientific mind----"

"They are all just rocks," finished Dick with a grin.

"I have had unusual success to-day," said the professor, who appeared
not to have heard the remark. "I must have at least fifty pounds of
specimens on my back at this minute."

He broke off suddenly. The next moment he darted off to the side of
the road and chipped off a fragment of rock from a bank that overhung
it.

"This is lucky, indeed," he exclaimed, holding it up to the light so
that some specks in the gray stone sparkled. "An extremely rare
specimen of mica that I had no idea existed in this part of New
England."

The odd little man opened his bag and introduced his latest
acquisition into it While he was doing this Dick had been explaining
to the boys:

"He's a queer character. Professor Jerushah Jenks. They say he's a
great authority on mineralogy and so on. I interviewed him on