"Then why didn't they take the sapphire?"
"Exactly. By the way, is the stone still at Scotland Yard?"
"Yes."
"Has it been tested?"
"No."
"Have it examined by the most expert man you can find. I think you will find it is paste, a wonderful imitation, capable of standing some tests—but still paste."
"Then why did Mr. Ratcliffe—an expert in gems, remember—treasure it so carefully?" I asked.
"He didn't," Quarles answered shortly. "It is obvious that a man who possessed such stones as were found in that packet at the bank would certainly not make such a mistake; yet he was apparently playing with his treasure when he met his death. My theory had three points, you see. First, the sapphire was the sole object of the robbery; secondly, the thieves had substituted an exact duplicate for the real stone; thirdly, the stone must have some special fascination for Mr. Ratcliffe, or he would have put it in the bank for safety as he had done with others."
"An interesting theory, I admit, but——"
"Wait, Mr. Wigan. I have said something about my methods. I began to look for facts to support my theory. You remember the cook-housekeeper?"