"I know. Lock-box No. 82 was constructed on the same principle in miniature, the letter-slit being placed in such a position that anything deposited in the box fell behind the mirrors, the whole interior remaining apparently visible through the glass front, and presumably empty. The owner of the box would naturally glance into it before actually using his pass-key. Obviously, it were a waste of time to go through the form of opening an EMPTY box, and so poor Sydenham never got any of the letters that were daily deposited there, for the receptacle is a large one and the secret place behind the mirrors was almost full. The action of unlocking the box operated upon an interior mechanism that swung back the mirrors at the same instant that the door was pulled open. After seeing my dummy disappear, I tried the experiment, and was amply rewarded. "There isn't much more to tell. When I saw the letters lying there I knew that it was all right so far as the girl was concerned. I had only to acquaint Miss Sandford with the circumstances in the case to secure her further co-operation, for, of course, she had never ceased to believe in her lover. She prepared and sent the message which you saw delivered to Sydenham in Sandford's office this afternoon. "But it was not the same as the one received by him on the actual January 9th. That contained a word, 'yes,' and was signed by her initials; this second one consisted simply of a sprig of heliotrope." "Do you understand the language of flowers? The heliotrope means, 'Je t'adore,' and Sydenham understood it instantly, as you saw." "Yes; but why--" "To repeat the original message would not have impressed him as I wished; it would simply have seemed part of the illusion which he knew perfectly well we were endeavoring to create. The problem was to suddenly startle him by a real communication from V. S., and, above all, to have it of such a nature as to convince him that the cloud between them had finally lifted. Now, without trust and confidence, true love is impossible. The message of the sprig of heliotrope told him all that he had been hungering and longing to hear throughout these terrible two months; the shock was sufficient to drive the normal consciousness from its seat and permit the subliminal self to take control. In other words, it practically put him back in the identical mental mood of the afternoon of January 9th, and that was the crucial point of the whole experiment. Anything more?" "Who sent the false telegrams?" "Of course, you would ask that. I don't know." "Such a monstrous wickedness! It is inconceivable." "Yes, unless we admit the existence of a spirit of pure malevolence seeking to drive an innocent man to self-destruction for no other motive than that of doing evil for evil's sake. That such an intelligence has been active in this case is certain; or how explain the cheat of the letter-box, a necessary factor in the problem, as you will admit?" "But you don't know."