"On the contrary," replied Marten, "they are all dead—but the case is solved." "Dead!" repeated Forrester. "Yes," said Marten. "You killed Prentice with his own gas. Lucy escaped and went to warn the chemist. He, probably realizing that escape was impossible, killed both Lucy and himself with the gas. We found their bodies when we went to his place. The most intricate case of my career, therefore, has been satisfactorily solved and a terrible menace removed." "And Prentice’s family," murmured Forrester. "What about them?" "Mrs. Prentice turned everything over to the M.B.A. She had a small private income, however, which the association refused to touch. She and her daughter, Diana, left this morning to go to Europe, where they will remain indefinitely. "Now," terminated Marten, rising, "I am sure that I have cleared Miss Sturtevant of any suspicion in your eyes, and I will leave you two together to solve any further problems you may have in your own way." Marten shook hands with Forrester and Mary Sturtevant and left the room. A minute later they heard the thrumming of the engine as he drove away in his car. THE END