rocks.

"And from perfectly massive rocks to the most perfectly stratified
sediments there are represented a considerable variety of masses
belonging to different ages--a very complete section of the Palaeozoic
and a rather full sequence of the latter deposits which recline
against the older strata."

"Yes, sir," agreed Ned meekly.

"A-h-e-m. And now having thus enlightened you, we will proceed with
our quest for something to eat. I trust my explanation has been
perfectly clear to you all?" queried the scientist, with the suspicion
of a twinkle in his eyes.

"With all due respect to you, sir, I must confess that I didn't
understand a word of it," answered Tad boldly.

"I hadn't the slightest idea that you did," retorted the Professor,
with a hearty laugh. "Our friend, Master Stacy, appears to be the
only one of you who grasped the scientific truths."

The boys shouted with laughter.

Ned Rector proposed three cheers for Professor Zepplin, which were
given with a will.

Stacy, rather crestfallen, joined in the cheering, weakly, however.

"It is well to give thought now and then to more serious matters,