All at once, with astonishing suddenness, he came out into the opening and there before him was the grave, the headstone gleaming gray in the dim light. Frank paused. Involuntarily he listened. He had not forgotten how, on his other visit to the spot, both he and Browning had seemed to hear a mysterious whisper in the air, had seemed to hear a rustle down in that grave, as if the murdered man turned restlessly. Without knowing why he did so, Frank listened again. "Look!" He started, for it seemed that he had heard that whisper. He glanced all around. Silence in the woods. Not even the rustle of a leaf. How lonely it was! "Look!" Again that word, coming from he knew not where. At what should he look? What did it mean? Then he told himself that it was all his imagination--he had heard no whispered word. He advanced toward the grave; he stood beside it. "Look!" Was it imagination? This time the whisper sounded amazingly clear and distinct. "Look at what?" In spite of himself, he spoke the words aloud. He did not expect an answer, and he gasped for breath when it came: "The stone!" A quiver ran over Frank Merriwell's body. Of all the mysteries on this island, the mystery of this black whispering glade in the woods was the greatest. He bent forward and looked at the stone. There were fresh chips on the mound, and at a glance he saw that the name "Rawson Denning" had been chiseled out. Below it another name had been cut into the stone, so that the inscription now read: "Sacred to the Memory of Frank Merriwell." CHAPTER XXV. SEARCHING FOR FRANK. As time passed and Frank did not return, the boys began to grow restless and anxious. "I don't like it," declared Diamond, pacing the beach, upon which the tide was washing higher and higher as it came in. "I did not think much of letting him go away alone. We all know what happened to him once when he was alone on this island." "He knows it himself," said Hodge; "and it is mighty hard work to catch him twice in the same trap." "Oh, he's shrewd enough, but he can be overpowered by numbers. What do you think about it, Browning?" Bruce was stretched on the sand, his head pillowed on his coat, which lay on a rock. "I'm not going to think for an hour," he grunted. "Too much trouble." "Oh, your laziness makes me disgusted!" snapped Diamond. "Huah!" came in a puff from the big fellow. "Something seems to be gnawing you still." "Poys," broke in Hans, who still looked sad and weary of living, "I made der biggest mistook uf your life ven I let Vrankie go avay alone all py himseluf to chase dot liddle defil mit der saucy mouth--you heard me vawble!" "If he had fallen into trouble, he would have done some shooting to let us know." "But should we have heard it, Hodge?" asked Diamond. "The island is not very large."