The life-giving oxygen was there in its tube, at his very lips, but here in this dangerous light-air pressure, Hal had not been able to assimilate all the oxygen that he needed. The human lungs, built to take in the amount of air needed at ground levels, had balked at having to take in five times the usual volume as was necessary in the heights of the stratosphere. And all in an instant, the exhaustion of air-starvation had claimed the flyer as its victim.