I need not go into the intricate calculations necessary to provide for all the conditions of the problem. Fortunately for my purpose the walls of the projected addition lay at a favorable angle for the carrying out of my designs, and I had only to work out the correct position for the windows and make the proper allowance for the overhang of the roof cornice. The stained glass was made from my own drawings, and I personally set the bullseye lens in its appointed place. The work was finished in May, 1861, and I should have liked to have made a test of my apparatus before Yardley's return from abroad; if there had been any error in my calculations and measurements it would be difficult, later on, to trump up an excuse for making the necessary structural alteration. But, as it turned out, I had made no mistakes. However, Yardley forestalled my intentions by appearing at the "Hundred" early in May. I bade him welcome, and showed him my completed work. He was pleased and said so, frequently and warmly. I could only smile in acknowledgment of his plaudits and fulsome thanks. June the twentieth of that same year I sat in my observation post on Sugar Loaf. Through my high-powered telephoto lens I saw Yardley come into the room and sit down at his desk. It was then ten minutes of twelve o'clock. Five minutes later, what looked like a streak of purple flame leaped through the semi-darkness of the room, and Yardley Hildebrand toppled to the floor. The apparatus had worked with meticulous exactness, and Evelyn Mansfield was avenged--at least in part. Since then I have watched two others of that black line of Hildebrands go to their doom--Randall and Horace. Poor spirited creatures, both of them, and hardly worthy to receive the accolade of my splendid Sigma ray. Randall held his sovereignty for just a year, but Horace had the devil's own luck. Cloudy days saved him, together with one quite unforeseen contingency, an eclipse of the sun on June 21, 1864. On June 20 and 21, 1865, there were heavy rains, and I was furious. But the twenty-second was clear and fine, and lo! he, too, was gathered to his fathers.