"Hello, Steve!" The chief pilot smiled as he shook hands cordially. "Glad to see you again--but don't try to kid the old man. I'm simple enough to believe almost anything, but some things just aren't being done. We have been yelling, and yelling hard, for trained computers ever since they started riding us about every one centimeter change in acceleration, but I know that you're no more an I-P computer than I am a Digger Indian. They don't shoot sparrows with coast-defense guns!" [Illustration] "Thanks for the compliment, Breck, but I'm your computer for this trip, anyway. Newton, the good old egg, knows what you fellows are up against and is going to do something about it, if he has to lick all the rest of the directors to do it. He knew that I was loose for a couple of weeks and asked me to come along this trip to see what I could see. I'm to check the observatory data--they don't know I'm aboard--take the peaks and valleys off your acceleration curve, if possible, and report to Newton just what I find out and what I think should be done about it. How early am I?" While the newcomer was talking, he had stripped the covers from a precise scale model of the solar system and from a large and complicated calculating machine and had set to work without a wasted motion or instant--scaling off upon the model the positions of the various check-stations and setting up long and involved integrals and equations upon the calculator. The older man studied the broad back of the younger, bent over his computations, and a tender, almost fatherly smile came over his careworn face as he replied: "Early? You? Just like you always were--plus fifteen seconds on the deadline. The final dope is due right now." He plugged the automatic recorder and speaker into a circuit marked "Observatory," waited until a tiny light above the plug flashed green, and spoke. "IPV _Arcturus_; Breckenridge, Chief Pilot; trip number forty-three twenty-nine. Ready for final supplementary route and flight data, Tellus to Mars." "Meteoric swarms still too numerous for safe travel along the scheduled route," came promptly from the speaker. "You must stay further away from the plane of the ecliptic. The ether will be clear for you along route E2-P6-W41-K3-R19-S7-M14. You will hold a constant acceleration of 981.27 centimeters between initial and final check stations. Your take-off will be practically unobstructed, but you will have to use the utmost caution in landing upon Mars, because in order to avoid a weightless detour and a loss of thirty-one minutes, you must pass very close to both the Martian satellites. To do so safely you must pass the last meteorological station, M14, on schedule time plus or minus five seconds, at scheduled velocity plus or minus ten meters, with exactly the given negative acceleration of 981.27 centimeters, and exactly upon the pilot ray M14 will have set for you."