"And 'that wretched Callister' bids you say your prayers, young man!" cried a deep voice behind them. "In digging that hole you have dug your grave. Prepare to lie in it now." The four boys sprang back, Frank leaping from the hole. There, amid the old boxes and barrels in the dim light, the forms of two men could be seen with cocked revolvers pointed--one directly at the head of Barney, the bootblack, the other at the head of Frank. CHAPTER XXV. THE MYSTERY OF TRINITY CHURCH-YARD EXPLAINED AT LAST. At the sight of Elijah Callister and his companion standing before him with cocked pistols in their hands amid the shadows of the cellar, Frank Mansfield sprang from the hole in which he stood. Seizing the pick-ax, he advanced bravely toward the man who long had been the persecutor of himself and his afflicted family, heedless of the glittering muzzles of the revolvers pointed directly at his head. Barney the Bootblack, Garibaldi and Sandy had meanwhile sought refuge among the boxes and barrels, the little Italian making the cellar ring again with his cries of fear. "Shoot, if you dare, Elijah Callister!" cried Frank, with proudly curling lip. "You helped to kill my father, you drove my mother mad. Murder me, if you dare! There is justice for such as you. As God hears me, it will descend swift and sure upon your sinful head." "Be careful, Lije," whispered the man by his side. "There are three of them--we can't kill them all. By Heaven! the lad is right, there has been murder enough. Beside, he is my nephew, poor Helen's son, and I say he shan't be killed!" It was Reuben Tisdale, the burglar, the husband of the dead Mrs. Marley, by whose hand that unfortunate creature came to her untimely end in the little house in the rear of the Donegal Shades. As he spoke these words, with one blow he struck the pistol from the hands of Elijah Callister, his own hand falling to his side. "Meddling fool!" cried the broker, fiercely, springing upon him. "The treasure for which we have risked so much lies uncovered before us at last, and now you would spoil it all! That boy must die or we are ruined! I tell you he has been a spy upon us; he has----" "Stop! He is my son, Elijah Callister, and he shall live! Harm one hair of his head at the peril of your life!" Through the dark passages of the cellar the words resounded. Instantly there burst upon the scene a blaze of light. It rested upon the boxes and barrels, it fell upon the cobweb-hung beams overhead, and, glancing back, lit up the faces of Callister, Tisdale and Frank with a strange, unearthly glare. With a loud cry the bank burglar, heedless of the blow aimed at him by his infuriated companion, sprang back. "Lije! Lije! Look! look! It is Maria's ghost again!" he cried, frantically, clapping his hands before his face to shut out the light which met his gaze.