This ape, some four feet in height, was exceedingly powerful and more than usually imitative, but was not naturally vicious. Any action done in its presence the animal would be certain to repeat at the first opportunity; but having done so, it did not repeat it again unless the action was performed again. The action of strangling a man in his sleep by means of a cord was performed before the ape, and afterwards the animal was allowed to steal through the hole in the chimney. The result was that Greaves was found dead. It was intended that Quarles should die in a like manner, and special pains were taken with the ape to insure success. The action was performed before the animal in every detail more than once, and it was kept in strict confinement until the right moment came. The ape was out of my sight, but I chanced to see the imitation in progress on the Thursday night through the glass, which had unaccountably been left open for some minutes after it had been tried to see that it was in working order. I saw only dimly because the imitation was being done by the light of a single candle, and that shaded as much as possible, to suggest to the ape the gloomy conditions of the room in which it was to repeat its lesson. Let into the wall of the room in the boarding-house there was a glass backing on to the one in the haunted room. A small handle swung aside the back, which was common to both, and the looking-glass became a window from one room to the other. When he fired Quarles evidently hit the ape. Mad with pain, the animal dashed back through the hole in the chimney and attacked the doctor, who was probably taken entirely unawares, as he was looking through the glass to see what the revolver shot might mean. The ape went through its part of the performance, and the doctor fell a victim to his own diabolical ingenuity. The wounded animal had to be shot before any one could get near the body. Some people have declared that Dr. Randall was a madman, but I think Quarles' answer hit the truth. "Of course, in a sense, all criminals are mad," he said, "but Randall was the sanest criminal I ever came in contact with." CHAPTER V THE DIFFICULTY OF BROTHER PYTHAGORAS Whether it was my statement that criminals had grown cleverer than they used to be which aroused Quarles's interest so effectually, or whether it was that success made him thirst for further fields to conquer, I do not know. I do know, however, that he grew restless if any considerable time elapsed without my having a clue worthy of his powers. As it happened we had two or three cases close together which stretched his powers to the utmost, and the extremely subtle manner in which he solved them shows him at his best. When I sent him a telegram from Fairtown, merely requesting him to join me there, I felt certain he would come by the first available train, and was at the station to meet him.