The former sailor showed the girls other treasures from the sea; huge fluted specimens and tiny, delicate shells. Amazed at the variety, Nancy asked Salty if he had collected them during his travels.

            "No." The clam digger laughed. "Mr. Heath gave 'em to me."

            The name startled Nancy. "Not Walter Heath?"

            "No. Ira Heath-Walt's father," Salty answered. "He gave me the shells when he had his button factory on the inlet."

            "A button factory near here?" Bess asked in surprise.

            "It's been closed for years. It was shut down when the supply o' fresh-water mussels gave out. Mollusk mother-of-pearl shells are used, you know, to make pearl buttons."

            "What became of Mr. Heath?" Nancy inquired.

            "Ira was born in England an' went back there on a visit. He died in London. His son Walt was left in charge here."

            "Did Ira build the castle?" Bess asked.

            Salty nodded, warming to the story. "Yes, Heath Castle was built to look like one o' those fancy English places. The gardens were beautiful-a sight to set your eyes ablaze with admiration. Stone walls everywhere, with flowers an' vines, an' all kinds o' trees from everywhere in the world."

            Nancy was becoming more eager every minute to see the estate.

            "But for me," Salty went on, "the place is too lonesome. No houses close by. The old gent built it 'bout a mile up the river from the button factory. Walter lived in it, too, an' he used to do some o' his scientific experimentin' there."

            "What kind of experiments?" Nancy asked.

            "Don't know," said Salty. "Since Walt died, no one ever goes near the castle, or the factory on Harper's Inlet."

            "Harper's Inlet?" Nancy repeated thoughtfully. "Someone must have been there yesterday."