Astounding Science Fiction, British Edition — page 126: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

BRASS TACKS Dear Sir: SUBJECT: The very interesting “MISSION OF GRAV- ITY.” QUESTION: A slight oversight— or am I just not as- suming enough? Briefiy, | Flyer Lackland is down in Mesklin to salvage a valuable remote-control rocket which failed to heed its “return” call. Accidentally stranded in a heavy armor under three gravities, Lackland says, “. . . If there was ever born an Earthman who could walk eighteen miles . . . I’m certainly not the one. My air will last indefinitely with these alga gills . . . but I’d starve to death before I made the station.”’ Eighteen hours later he is back at station. Eighteen hours under three at- mospheres normal Earth air requires a very definite step-by-step decompres- sion period—running into hours de- pending on amount of exertion, water temperature (air temperature) or cramped position. If that “alga air” is pure oxygen, our hero is in for a lovely case of oxygen poisoning. Let’s assume Lackland’s station, suit, and tank are all one Earth’s atmosphere (approx. 14.7) pressure stressed. : “Closing his helmet, Lackland opened the door of his vehicle. A faint—no violent swoosh!—swirl of white crystal followed him out.” Assume a circular door twenty- eight inches in diameter, with one atmosphere pressure inside—and three outside, Now exert some sixteen hundred pounds force, and open gently. In closing I want to say that I enjoy Conmiclooolkks.c© im