Hardly knowing what to believe, I followed him from the house and to a huge barnlike structure, over a hundred feet high, which stood nearby. He opened the door and switched on a light, and there before me stood what looked at first glance to be a huge artillery shell, but of a size larger than any ever made. It was constructed of sheet steel, and while the lower part was solid, the upper sections had huge glass windows set in them. On the point was a mushroom shaped protuberance. It measured perhaps fifty feet in diameter and was one hundred and forty feet high, the Doctor informed me. A ladder led from the floor to a door about fifty feet from the ground. I followed the Doctor up the ladder and into the space flier. The door led us into a comfortable living room through a double door arrangement. "The whole hull beneath us," explained the Doctor, "is filled with batteries and machinery except for a space in the center, where a shaft leads to a glass window in the bottom so that I can see behind me, so to speak. The space above is filled with storerooms and the air purifying apparatus. On this level is my bedroom, kitchen, and other living rooms, together with a laboratory and an observatory. There is a central control room located on an upper level, but it need seldom be entered, for the craft can be controlled by a system of relays from this room or from any other room in the ship. I suppose that you are more or less familiar with imaginative stories of interplanetary travel?" * * * * * I nodded an assent. "In that case there is no use in going over the details of the air purifying and such matters," he said. "The story writers have worked out all that sort of thing in great detail, and there is nothing novel in my arrangements. I carry food and water for six months and air enough for two months by constant renovating. Have you any question you wish to ask?" "One objection I have seen frequently raised to the idea of interplanetary travel is that the human body could not stand the rapid acceleration which would be necessary to attain speed enough to ever get anywhere. How do you overcome this?" "My dear boy, who knows what the human body can stand? When the locomotive was first invented learned scientists predicted that the limit of speed was thirty miles an hour, as the human body could not stand a higher speed. To-day the human body stands a speed of three hundred and sixty miles an hour without ill effects. At any rate, on my first trip I intend to take no chances. We know that the body can stand an acceleration of thirty-two feet per second without trouble. That is the rate of acceleration due to gravity and is the rate at which a body increases speed when it falls. This is the acceleration which I will use.