spaceship propelled by an experimental antigravity drive. Burl is told that, unlike Cavorite, which H.G. Wells described in his 1901 novel First Men in the Moon, the drive on A-G 17 (also called Magellan) is an active device, requiring thermonuclear reactors to provide the necessary power. The drive can produce attraction as well as attraction of gravitational fields and it can concentrate the force, enabling the ship to produce tremendous accelerations. With Burl on board, the crew takes the ship into space and grabs the Sun's gravitational field to pull the ship onto a trajectory that will take it to Venus. An error in their understanding of the A-G drive leads them to shoot past Venus, so they go to Mercury instead. There, protected by parasols, the wrecking crew invades the Sun-tap station and Burl shuts it down. An alarm flashes and some time later, just as the men have finished photographing the station, the station destroys itself, saving the Earthmen the need to bomb it. They then head out to Venus. They find the Sun-tap station on Venus sitting on a wide mudbar in the middle of a shallow, planet-wide ocean. Inside the station Burl shuts down the alarm and then shuts down the station. Then he and his two companions must fight their way past a large, flesh-eating amoeba on their way to the helicopter that will take them back to Magellan. Mars is their next stop. While they pass close to Earth they learn that the Sun-tap transmissions have been traced and they point to Pluto as their destination. On Mars the men discover that the Sun-tap station has been built underneath a Martian city. Again Burl shuts down the alarm and then the station as the other men on his team take pictures and set a tactical atomic bomb to destroy the place. On their way out Boulton fires his gun at what looks like another alarm and is hit by a bolt of electricity. Fighting their way through a mob of the ant-like Martians, they return to Magellan and set course for Jupiter. On the way Boulton tries to sabotage the ship, but when Burl grapples with him in an effort to stop him both men are knocked out by a flash of light. When they regain consciousness they find that Boulton is back to normal, the electric contact with Burl having freed him from