Sandy nodded at Dick’s exclamation.

“Miss Serena saw her run in her uniform,” contributed Larry.

“How did you discover she was Jeff’s wife?”

“Talking to farmer boys—what they didn’t know, they found out from their older sisters when any of them were picking up early potatoes or snipping asparagus or digging up onions.”

“My—golly—gosh—gracious——”

Sandy agreed with Larry’s exclamations but urged his chums to leave the hangar: they knew all it could tell them. He wanted to replace the book he had used and get away from the hangar for awhile.

In the old, disused house, to which Mr. Whiteside had secured a set of keys for them so they need not hang around the grounds until there was work to be done, they talked in low tones. Sandy believed that Jeff had coaxed his wife to put acid on the gems in the London hotel, as had been done.

“He might be as much of a fanatic as that,” admitted Larry, but not with any great delight—he had always liked Jeff. “He is as superstitious as a heathen.”

“But the maid knew those weren’t the real gems!” Dick remarked.

“How do we know she did?”