The ventilator and the bell-rope which hung down to the bed drew my attention. The discovery that the bell did not ring, and that the bed was fastened to the floor, gave me an idea that the rope was there as a bridge for something to pass through the opening and to come to the bed. The idea of a snake occurred to me at once, and when I recalled that the doctor kept animals from India, I felt that I was probably right. The idea of using poison which could not be discovered by any chemical test could occur to a clever man who had lived in India.