Looking out of the porthole, I saw Spartan in his spacesuit, standing in the red sand, the first human being to set a booted foot on Mars. He walked gingerly a few paces, then set up a small instrument, pressed buttons and read dials. Then he reached down, picked up a handful of sand and tossed it in the air. A playful gesture for Dr. Spartan. But why shouldn't he be elated? He had led the first voyage from earth to Mars. The sand he threw seemed to drift down ever so slowly--a little pebble taking fully a second to fall five feet. On earth it would have fallen 16 feet in that short space of time. Spartan stood erect and silent, his helmeted eyes fastened on the oasis to the east. For a moment I forgot his arrogance, his murderous heart, and his determination to kill me and to take Gail. He was a representative of the earth, not an individual now. Then he marched back to the ship, his evil manner suddenly accentuated. Every move, every gesture showed his utter contempt for others. He was the kind of man who was able to make you mad by merely saying, "Good morning." He entered the ship and closed the locks. Then he came up the ladder to the control room and twisted a valve which released the air in the ship. Not until that moment did he address us over his helmet transmitter. "The Martian atmosphere is much like the earth's," he said. "It has oxygen, nitrogen, a small amount of carbon dioxide and minute traces of water vapor. Possibly it also contains inert gases--the heavier ones. I doubt if there's much helium here. It is not poisonous, although it does contain a small amount of ammonium vapor. However, it is too thin to breathe. We may be able to pump air into our ship to replenish our air supplies, should they get low, but we can't go out of the ship without spacesuits." Talk of ammonia in the atmosphere led to new avenues of speculation. Scientists have suspected for many years that a kind of life might exist on compounds of ammonia, instead of water. There are indications that the first life on earth may have absorbed ammonia from sea water, instead of oxygen, for some such compounds are still present in proteins. As oxygen grew more plentiful on the earth, life adapted itself to water and oxygen. On Mars this stage may not have been reached, although it seemed rather unlikely. As rare as the oxygen was, Dr. Spartan said, the amount of ammonium vapor in the air was small. Soon the cabin was filled with air. We descended the ladder and began to unpack the materials. Axel remained in the control room, alert for Martians, listening to the radio which now was filled with a variety of weird whistles, chirping noises and rattles. "They know we've landed," said Axel. "I can't understand these Martians, but I have a feeling a lot of this is about us." "We can defend ourselves," said Spartan. "What if they have nuclear weapons?" I asked. Dr. Spartan shrugged. "It's not impossible," he said. * * * * *