"A MYSTERY.--Yesterday morning at six o'clock an unknown young woman of about twenty-five or thirty years of age, of medium height, plump form, fair complexion and yellow hair, clothed in a rich suit of widow's mourning, was found in a state of coma in the ladies' dressing room of the Hudson River Railway station. She was taken to St. L----'s Hospital. There was nothing on her person to reveal her name or address." "That must have been Mrs. Stillwater," said old Aaron Rockharrt. "I think there is no question of it," replied Cora. "No doubt the poor child was suddenly seized with one of her terrible neuralgic headaches, caused by the pressure of that infernal crowd at the gate, and she stole away, as before, lest she should disturb us and prevent our journey; the most self-sacrificing creature I ever met. No doubt she meant to telegraph to us, but was prevented by the sudden reaction from agony to stupor. Ah! I hope it is not a fatal stupor." "I hope not, sir." "Cora!" "Yes, sir." "We must leave for New York by the next train. If Sylvanus is not free to go with us, he can follow us. Come, let us go down and get some breakfast." Cora arose and went with her grandfather down to the breakfast room. When they had taken their places at one of the tables and given their orders to one of the waiters, old Aaron Rockharrt drew a time table from his pocket and consulted it. "There is a down train stops at Garrison's at 10:50. We will take that." As soon as they had breakfasted, and as they were leaving the table, another telegram was handed to Mr. Rockharrt. He opened it and read as follows: BLANK HOUSE, New York, May ----, 18-- The missing lady is in St. L----'s Hospital. M. MARTIN. "It is true, then! true as we surmised. Mrs. Stillwater was the unknown lady found unconscious in the dressing room of the Hudson River Railroad and taken to St. L----'s. Cora!" "Yes, sir." "Go and pack our effects immedately. I will go down and settle the bill and leave a letter of explanation for Sylvanus. Get your bonnet on and be ready. The carriage will be at the door in twenty minutes." Cora hurried off to her room and to her grandfather's room, which adjoined hers, to prepare for the sudden journey. She quickly packed and labeled their traveling bags, and rang for a porter to take them down stairs. Then she put on her bonnet and duster and went down and joined her grandfather in the parlor. "Come," he said, "the carriage is at the door and our traps on the box. I have written to Sylvanus, telling him to join us at the Blank House, where we will wait for him." He turned abruptly and went out, followed by Cora. They entered the waiting carriage and were rapidly driven down to the ferry. The boat was at the wharf. They alighted from the carriage and went on board.