"Always when he's getting specimens," Dick whispered back.

By this time the professor, his eyes agleam over his latest discovery,
was back at the side of the car.

"Ah, my beauty, I have you safe now," he said, patting the side of the
bagful of specimens. "Boys, this is my lucky day."

The boys could hardly keep from smiling at the little man's delight.
It appeared hard to believe that anyone could find pleasure in packing
about a sackful of heavy rocks on a hot day. But the professor's eyes
were sparkling. It was clear he considered himself one of the most
fortunate of men.

Dick introduced the boys and, to their surprise, the professor
declared that he had read of their various adventures and inventions.

"We are actually fellow adventurers in the field of science," he
cried, rattling his bag of specimens enthusiastically. "Some time I
should like to call on you and see your workshops."

"You will be welcome at any time," said Jack cordially, and then the
professor declared that he must be getting home.

"If we are going your way we can give you a ride," said Tom.

"Thank you, I'll accept that invitation. But what an odd-looking
automobile you have there."