Since the mine was located near the equator, this alternation of the whole crew was necessary to reduce exposure to the miniature sun that provided so little useful heat, yet whose ultra-violet pierced the cloudless, thin atmosphere with vicious intensity.
No one went hungry, but as the weeks passed the seeming variety of food rations disappeared. The monotony of dehydrated vegetables and meats palled. But worst was the silence. For ten hours each day almost no communication passed among the workers. All breathable oxygen had to be extracted from the oxides of minerals, and the by-product oxygen from the mining operation was barely enough to supply the total demands of their masks. So even the inside working areas were left to Mars' unbreathable gases, and masks could be removed only in off-duty quarters.
Chief occupations in off-hours were games of chess, reading, writing and activities that used a minimum of conversation. No one felt like talking much after a full shift of sucking hard at oxygen to keep up with his body's demand. Although the lessened gravity appeared to make all physical labor easy, Duncan could never remember such complete fatigue at the end of a working day. He ate, worked, played chess and slept 10 hours a day.
The women replacements had disappeared into their compound and were seen no more. He wondered at the type of indoctrination they were getting. Did it include an item concerning the use of loving hands? Strangely, the men made no reference to the women, and he was reluctant to draw attention by broaching the subject.
The living quarters, mess-hall and recreation spaces were grouped intimately, but placed in such a manner that windows and entries allowed no casual glimpses of the women from the men's areas. Complete security in the matter of segregation appeared to be guaranteed on the honor system alone. All 140 men slept in one long bunk-room, all 20 women in another.
Intelligent men are not easily bored, but Peter Duncan discovered a certain restlessness developing among the new men during the fourth month. There was a tendency to break off in the middle of a chess game, or to speak tersely. Duncan ascribed this to a phase of adjustment, because the second term crew seemed better tempered.
Then it began to bother him. He found himself developing an unreasoning impatience. He began using profanity at slight annoyances. The stiff soreness of chest, neck and back muscles became chronic, and he began laying awake listening to his own rapid breathing, begrudging every inhalation of his overworked lungs. The devil with expense! Why didn't they at least pressurize the sleeping quarters so a man could get some decent rest?
He recognized the symptoms of increasing irritability in himself as it distracted him even during his work. But he couldn't put his finger on the cause. It grew worse. During the twelfth month he reached a stage of exasperation that almost cost him his life.
He was tightening a bolt on one of the spindles. The second time his wrench slipped off the nut he squared away and threw the spanner at the horizon. Too late he saw his crew-mate, geologist Magnus Porter. Horrified he watched the wrench arc three times as far as it would have on earth, and strike Porter in the face. He went down.
When Duncan reached him the scientist's face was gushing blood, and his smashed mask hissed its charge into the sterile air. Fortunately, they were on the camp side of the pits, only two hundred yards from sickbay. Porter weighed no more than a blanket roll, and the odds seemed good at first. But before Duncan had bounded half the distance his lungs pumped to the bursting point. His vision dimmed, and his legs faltered. He tore off his mask, pressed it to Porter's face, gulped a chest full of dead air and screamed for help.