They began to feel the gravitational attraction of the miniature world, and they had to bolster rocket fire to combat it. Unlike Venus, Mercury could not be avoided in this flight. Steve watched the gauges, especially the refrigerator dial. The latter was holding up well under this maximum barrage of heat from Sol, but there was still an oppressive hotness that reached through the laboring artificial coolness and penetrated Steve’s pores like insidious rays. “If the _Comet_ isn’t superior to Dennis’s in any other way, it’s made of better heat-resistant alloy,” Bart had said with self-assurance before leaving Earth. Steve wondered now if the proof of this assertion would be settled before both ships were beyond the sun’s reach. Hours later, when the _Condon Comet_ had passed Mercury, Steve was impelled to check on their rivals behind. For a moment he couldn’t find the ship on the TV screen. When he spotted it at last, by changing the direction of the movable screen, he was amazed to find the craft far below, hovering over the planet. “Bart!” Steve called. “It looks as if Jim and Pete are in trouble! They’re diving for Mercury and seem to be heading for the terminator line between the dark half and the light!” Steve wished there were some kind of radio communication between the ships, but electrical interference from the sun made radio impossible on these round-the-sun races. “We’ve got to go down there, Bart,” Steve said. “We haven’t won yet, Steve. There’s still the record to beat.” “Will you stop thinking about records!” Steve retorted. “There are a couple of men down there in trouble!” “Did they stop for us?” Bart bit out. “It’s probably only a trick to lure us down so that Dennis can make a quick getaway!” But Steve knew that his brother was not as cold-hearted as he pretended to be. Bart proved it in the next few minutes when he reluctantly turned the _Comet’s_ nose downward with a savage thrust of the upper tail jets. “You’ll never regret this,” Steve said. “I wonder,” Bart grunted, without satisfaction. As the ship moved strongly into Mercury’s gravitation field, Bart lined the automatic pilot up with the tiny speck on the rocky world below that was the _Dennis Meteor_. Then he and Steve strapped down on their protective couches for the grueling landing. Steve felt as though his chest were crushed under the rapid deceleration. It was the effect of a swiftly dropping elevator multiplied hundreds of times as the _Comet’s_ forward jets thrust against Mercury’s crust to brake the hurtling speed. Steve finally blacked out; he always did. When he came to, they had landed, and through blurry eyes Steve saw his brother struggling to release himself from his straps. They went to the port. The _Dennis Meteor_ was in bad shape, its prow crumpled into a huge face of rock. Its occupants could have been killed by the concussion, although there was a good chance that they were still alive if they had had time to strap down.