Grover drew his theories into shape.
“Naturally, with the real gem, Clark and Ryder made all speed to radio the prepared airplane. It met them. In Bombay, as he had no desire to be further involved, Potts discarded the false gem he had picked up.”
Then, proceeding on pure deduction, Grover felt that the Tibetans had discovered their real loss, had discerned that Roger and Tip had solved the intricate tunnel secret and had escaped. To write, with Roger’s discarded note book as a guide, in a semblance of his writing, was easy. The letter had come by fast mail steamers and had further confused him.
“Then the thief, with the gem in his fellow-worker’s possession, encountered difficulties,” went on Grover; “the man who had been intending to buy the jewel probably became frightened, afraid of the danger that the stone might bring around him. So many priceless jewels carry curses, or bring disaster, that he must have gotten ‘cold feet’ and a new buyer had to be sought. The gem, also, had to be secured, in case the Tibetans actually put into action their vengeful methods.
“Toby was working here. Ryder thought it a clever plan to have this former aide help him, and so he concealed the gem and had it innocently delivered here, but Toby, not as dumb as he was considered, suspected the truth, discovered the hidden gem, and on his own hook offered to sell it to a buyer he had known at Clark’s store.
“That made it necessary for Ryder to recover the gem quickly from the concealment no longer unsuspected here. He tried to get people away from upstairs, by detonating with his foot a torpedo under our office desk; but Astrovox, our scientific star-student, had been about to go home, frightened by some foolish combination of star-positions and a manifestation planned to scare him away. He walked in before Ryder could hide, recognized him—and the desperate man struck him.
“Soon thereafter he realized that in a list of some fifteen sounds made by Roger there lay the actual clue that incriminated him and no one else!”
“What was it?” asked Ellison anxiously or eagerly, Roger told himself.
“What Roger thought was claws-on-glass. His very first sound-clue. With that on a list, and in the clever head of the stock-room clerk, Ryder had two things to do quickly. He must get the gem, and he must either find a way to throw suspicion elsewhere or get Roger out of the way.”
Roger realized why many attempts had been made, like the one in the dark-room.