"We've been playing Zoo," he volunteered. "Gerda's been a lion, and gobbled me up, and she's been an elephant and given me rides, and we were both polar bears, and growled at each other. Listen how I can growl now--Ur-ur-ugh! Oh, and look what she's given me for my birthday! It comes from Germany," producing from his pocket a little compa.s.s. "Now if ever I get lost, I can always find my way home. See, I can show you which is north, and south, and east, and west."

"You'd better be going back, Gerda," remarked Dulcie grimly. "You know we're not allowed in the Castle grounds without a special invitation."

"I'll come through the side gate," replied Gerda, turning from Ronnie without even a good-bye. Deirdre and Dulcie dropped from the wall, and met their room-mate at the identical moment when she pa.s.sed through the turnstile.

"Well, of all mean people you're the meanest!" observed Deirdre. "I call it sneaky to take such an advantage, and go to play with Ronnie by yourself. We'd do it if it were allowed, but it isn't."

"I wonder his governess wasn't with him," said Dulcie. "He's generally so very much looked after."

"And as for going inside the Castle garden, it was most fearful cheek,"

continued Deirdre. "We, who know Mrs. Trevellyan quite well, never think of doing such a thing."

"What I call meanest," put in Dulcie, "was to try and curry favour with Ronnie by giving him a birthday present on your own account. Miss Birks said there were to be no separate presents: we were all to join, so that there'd be no jealousy--and you wouldn't subscribe. Oh, you are a nasty, hole-and-corner, underhand sneak! Have you anything to say for yourself?"

But Gerda stumped resolutely along with her hands in her coat pockets, and answered never a word.

CHAPTER VIII

A Meeting on the Sh.o.r.e

"D'you know, Dulcie," remarked Deirdre, when the chums were alone, "the more I think about it, the more convinced I am there's something queer about Gerda Thorwaldson."

"So am I," returned Dulcie emphatically. "Something very queer indeed. I never liked her from the first: she always gives me the impression that she's listening and taking mental notes."

"For what?"

"Ah, that's the question! What?"

"I certainly think we ought to be on our guard, and to watch her carefully, only we mustn't on any account let her know what we're doing."

"Rather not!"

"She's no business to sneak away by herself when we're all salvaging on the beach. She knows perfectly well it's against rules."

"She doesn't seem to mind rules."

"Well, look here, we must keep an eye on her, and next time we see her decamping we'll just follow her, and watch where she goes. I don't like people with underhand ways."

"It doesn't suit us at the Dower House," agreed Dulcie.

Though the chums kept Gerda's movements under strict surveillance for several days, they could discover nothing at which to take exception.

She did not attempt to absent herself, or in any way break rules; she asked no questions, and exhibited no curiosity on any subject. If possible, she was even more silent and self-contained than before.

Rather baffled, the girls nevertheless did not relax their vigilance.

"She's foxing. We must wait and see what happens. Don't on any account let her humbug us," said Deirdre.

One afternoon a strong west wind blowing straight from the sea seemed to promise such a good haul at their engrossing occupation that the girls, who for a day or two had forsaken salvaging in favour of hockey practice, turned their steps one and all towards the beach. As they walked along across the warren they had a tolerably clear and uninterrupted view of the whole of the little peninsula, and were themselves very conspicuous objects to anyone who chanced to be walking on the sh.o.r.e. Deirdre's eyes were wandering from sea to sky, from distant rock to near primrose clumps, when, happening to glance in the direction of the cliff that overtopped St. Perran's well, she was perfectly sure that she saw a white handkerchief waved in the breeze. It was gone in an instant, and there was no sign of a human figure to account for the circ.u.mstance, but Deirdre was certain it was no illusion. She called Dulcie's attention to it, but Dulcie had been looking the other way, and had seen nothing.

"Probably it was only a piece of paper blowing down the cliff," she objected. "How could it be anyone waving? n.o.body's allowed on the warren."

"It might be Ronnie and Miss Herbert."

"Oh no! We could see them quite plainly if it were."

"Gerda, did you notice something white?"

"I don't see anything there," replied Gerda, surveying the distance with her usual inscrutable expression. "I think you must have been mistaken."

It seemed quite a small and trivial matter, and though Deirdre, for the mere sake of argument, stuck to her point all the way down to the beach, the others only laughed at her.

"You'll be saying it's a ghost next," declared Betty. "I think you're blessed with a very powerful imagination, Deirdre."

Arrived on the sh.o.r.e, the girls found their expectations fully justified. Several most interesting-looking pieces of driftwood were bobbing about just at the edge of the waves, and with a little clever management could probably be secured, and would make a valuable addition to the stack which was to furnish their beacon fire. Jessie Macpherson, who possessed a pair of wading boots, was soon in command, directing the others how to act so that none of the flotsam should be lost, and marshalling her band of eager volunteers with the skill of a coastguardsman.

"Wait for the next big wave! Have your hockey sticks ready! Doris and Francie and I will wade in and try to catch it, then, when the wave's going back, you must all make a rush and try to hold it. Not this wave!

Wait for that huge one that's coming. Are you ready? Now! Now!"

The owners of the wading boots did their duty n.o.bly. They caught at the floating piece of timber and held on to it grimly, while a line of girls followed the retreating wave, and, making a dash, seized the trophy, and rolled it into safety.

"Oh, it's a gorgeous big one--the largest we have!"

"That was neatly done!"

"We've robbed old Father Neptune this time!"

"It's a piece of luck!"

"Of flotsam, you mean!"

"Three cheers for the beacon!"

"Hip, hip, hip, hooray!"

"Hooray! Hooray!" echoed Dulcie, then she looked round, and suddenly touched Deirdre on the arm.

In the midst of the general excitement Gerda had vanished. Where had she gone? That was the question which the chums at once asked each other. It was impossible that in so short a s.p.a.ce of time she could have scaled the steep path from the cove on to the top of the cliff. She must surely have run along the sh.o.r.e instead. To the east the great ma.s.s of crags formed an impa.s.sable barrier, but it was just practicable to round the headland to the west. Without a moment's delay they dashed off in that direction. They tore in hot haste over the wet sand, scrambled anyhow amongst the seaweed-covered rocks at the point, regardless of injury to clothing, and, valiantly leaping a narrow channel, turned the corner, and found themselves in a second cove, similar to the former, but larger and more inaccessible from the cliffs. They were rewarded for their prompt.i.tude, as the first sight that caught their eyes was Gerda, speeding along several hundred yards in front of them, as if she had some definite object in view.

"Shall I shout after her?" gasped Dulcie.

"Not for the world," returned Deirdre. "We mustn't let her know she's being followed."

"If she looks back, she'll see us."

"We'll hide behind this rock."