The thought flashed through my mind that doubtless M. Pigot was in the way of receiving a handsome present.

“There they are,” said Simmonds, and closed the bag with a snap, as Grady came in again.

“I’ve arranged for the box,” said Grady, “and one of our wagons is at the door.  I thought we’d better not trust a taxi—­might turn over or run into something, and we can’t afford to take any chances—­not this trip.  Simmonds, you go along with Moosseer Piggott, and put an extra man on the seat with the driver.  Maybe that Croshar might try to hold you up.”

The same thought was in my own mind, for Crochard must have learned of M. Pigot’s arrival; and I could scarcely imagine that he would sit quietly by and permit the jewels to be taken away from him—­to say nothing of his chagrin over his unfulfilled boast to Godfrey.  So I was relieved that Grady was wise enough to take no risk.

“You’d better get a receipt,” Grady went on, “and arrange that the valise is to be delivered only when you and Moosseer Piggott appear together.  That will be satisfactory, moosseer?” he added, turning to the Frenchman.

“Entirely so, sir.”

“Very well, then; I’ll see you in the morning.  I congratulate you on the find.  It was certainly great work.”

“I thank you, sir,” replied M. Pigot, gravely.  “Au revoir, monsieur,” and with a bow to me, he followed Simmonds into the outer room.

Grady sat down and got out a fresh cigar.

“Well, Mr. Lester,” he said, as he struck a match, “what do you think of these Frenchmen, anyway?”

“They’re marvellous,” I said.  “Even yet I can’t understand how he knew so much.”

“Maybe he was just guessing at some of it,” Grady suggested.

“I thought of that; but I don’t believe anybody could guess so accurately.  For instance, how did he know about those letters?”

“Fact is,” broke in Grady, “that’s the first I’d heard of ’em.  What is that story?”

I told him the story briefly, carefully suppressing everything which would give him a clue to the identity of the veiled lady.

“There were certain details,” I added, “which I supposed were known to no one except myself and two other persons—­and yet M. Pigot knew them.  Then again, how did he know so certainly just how the mechanism worked?  How did he know which roll of cotton contained that Mazarin diamond?  You will remember he told us what was in that roll before he opened it.”

Grady smiled good-naturedly and a little patronisingly.

“That was the last roll, wasn’t it?” he demanded.  “Since that big diamond hadn’t shown up in any of the others, he knew it had to be in that roll.  It was just one of the little plays for effect them Frenchies are so fond of.”

“Perhaps you are right,” I agreed.  “But it seemed to me that he handled that mechanism as though he was familiar with it.  Of course, he may have prepared himself by studying the drawings which no doubt accompany the secret memoir.  He may even have had a working model made.”