“Thick heads be blowed!” exclaimed Steve disgustedly.  “You were just yelling a lot of words that didn’t mean anything.  If you hadn’t kept on pointing we’d never have known what was up.  We all thought you had a fit.”

All’s well that ends well, however, and an hour after breakfast the incident was, if not forgotten, dismissed.  Joe reappeared, looking rather pale still, but announcing himself quite all right.  “I was nice and sick at my tummy,” he explained, “and now I feel fine.”

“Being sick at your tummy,” remarked Perry unkindly, “is quite the best thing you do, Joe.  If you can’t be sea-sick you go and try to drown yourself!”

Of course “Brownie” was allowed to surmise that he had done something rather big, and Joe thanked him very nicely, but Mr. Carnegie is still in ignorance of his exploit!

The two boats floated out of the pool about ten and set off for Bar Harbor.  The barely averted tragedy somewhat modified their regret at leaving Titania’s Mirror and Mystery Island.  Later, Steve and Joe tried to locate that island on the charts but without certain success.  There were so many islands thereabouts that neither dared to more than guess at the identity of the one they had visited.  Looking back at it from a distance of a half-mile they saw that it was in reality much smaller than they had supposed, being scarcely more than a huge rock pushed up from the ocean bed.  Ossie, who had a leaning toward geology, furnished the theory that Mystery Island was no more nor less than the top of an extinct volcano and that Titania’s Mirror was the crater.

“It probably sank, like lots of them did,” he elaborated, “and the sea wore away part of it and flowed into the crater.  I’m pretty sure that that rock we climbed out on this morning when we were swimming was volcanic.”

“Sure,” agreed Perry.  “It was pumice stone.  I meant to bring a bit of it along for you to clean your hands with.”

“I didn’t say pumice,” replied Ossie haughtily.  “It was more probably obsidian.”

“My idea exactly!  In fact, it had a very obstinate feeling.  It—­it left quite an impression on me!”

The Follow Me developed engine trouble that morning and they lay by for a half-hour or more while Tom Corwin toiled and perspired, argued and threatened.  It was well after two o’clock when they ran up the eastern shore of Mount Desert Island and finally dropped anchor in Frenchman’s Bay.  They ate only a luncheon on board and then clothed themselves in their gladdest raiment and went ashore.  They “did” the town that afternoon, mingling, as Wink said, with the “haut noblesse,” and had dinner ashore at an expense that left a gaping hole in each purse.  But they were both hungry and glad to taste shore food again, and no one begrudged the cost.

It was when they were on their way back to the landing that the glow of coloured lanterns behind a trim hedge drew their attention to the fact that someone was conducting a lawn party.  The imposing entrance, through which carriages were coming and going, met their sight a moment later and inspired Perry with a brilliant idea.