But when they returned some half-hour later, Miss Duke momentarily disarmed him by holding out her letter.

“You had better read that,” she said. “You may want to see it and there is nothing private in it.”

French was momentarily tempted to confess his action with the safety razor, but he saw that he must not divulge police methods, and taking the letter, he reread it and handed it back with a word of thanks.

“Did your father say he was going to Holland?” he inquired.

“Yes, it was one of his usual trips to the Amsterdam office. He expected to be away for two or three days. But I now think he had made up his mind—about—this—before he left. He said good-bye——”

She paused, her lip trembling, then suddenly flinging herself down on the sofa, burst into an uncontrollable flood of tears. “Oh!” she cried brokenly, “if only it hadn’t taken place at sea! I can’t bear to think of him—out there——” She sobbed as if her heart would break.

French saw that she had settled the matter of his procedure. In her present condition he could not probe her with subtle questions. There was nothing for it but to take his departure, and this he did as unobtrusively as he could, leaving her in Harrington’s charge.

He wondered who would take Mr. Duke’s place in the firm, with whom he would have to deal if his efforts to trace the missing diamonds became successful, and determined to call at the office and make some inquiries. He therefore took the tube to the City, and some half-hour later was mounting the steps of the Hatton Garden establishment.

Mr. Schoofs had already taken charge, and saw his visitor in his late principal’s office. The business, he believed, would belong to Miss Duke, though he had no actual reason to say so. However, Messrs. Tinsley & Sharpe of Lincoln’s Inn were the deceased gentleman’s solicitors, and no doubt fuller information could be obtained from them.

“I came over last night, and am just carrying on in the meantime,” he explained, “and you can deal either with me or with Mr. Tinsley.”