The tide was on the turn and big, angry crested waves were racing in over the flat sands. The horizon was a bright, clear strip of light above the brown sea, but dark clouds filled the rest of the sky. The world was full of wind. They were alone in a world of roaring and booming, a world in which the wind seemed a live and tangible thing as it whipped the sea into a fury, whirled microscopic grains of sand from the beach and whistled through the grass that was levelled round their heads. A few gulls wheeled and hovered against the force of the wind, while their plaintive mewing was tossed inland and lost in the tumult of the gale.

"That chap Vasson knows how to read the weather," David gasped. "Do you think we'd better get back to the Dolphin?"

"Yes, I do. I think we ought to look at the map again and check up on the hills which it shows. Come to think of it, David, Camber Castle is on a mound and we caught Miss Ballinger messing about round there. Then, the two windmills are built on mounds and both of those were marked on the map. And there's a gibbet on a little hill round here somewhere. Penny wants to explore that and - I've got it, I believe! There's one little hill marked specially and that's on Winchelsea beach just by those bungalows where the Ballinger lives!"

"Maybe you've got something there," David agreed. "Let's get back and rout out the others and see if there's anything we can do today... I hope it won't rain again, though."

"If it does," Jon replied, "we can all go up to our room and have a fire and make some plans for exploring all these mounds properly. Come on! Let's try for the bus," and they scrambled down from the dunes and were almost blown off their feet as they made for the road on the other side of the club-house.

The bus put them down by the river, and as they climbed the steps of Trader's Passage another scurry of rain rushed over the levels and lashed the sturdy walls of Rye that had stood fast and firm against so many gales.

Vasson was standing under the archway looking out to sea and nodded when he saw the boys.

"You were right about the weather, Fred," Jon remarked as he wiped the raindrops from his glasses. "I've never been in a gale like this before."

The porter shook his head. "Nor never may again," he muttered. "I've seen but two more like this and each time there's been trouble. And there'll be trouble tonight, I'm thinking. Now look," he said, pointing in the direction of Winchelsea beach. "That's where the levels seem to be lowest - back there behind those pink boxes they calls bungalows - and it's just along there from Cliff End to Camber where the bank is weakest."