Old Cobber's hand trembled slightly as he turned his tankbox so that his guns would point at the crew working outside. Wilson, atop the white hill, watching the men clear away the ammonia snow drifts from the jets of the rocket, was the first to notice the challenging position of Cobber in his tankbox. "Are you getting in or out of the airlock?" he radioed to Cobber. "Make up your mind." The old man's lips were dry and his voice was hoarse as he spoke into the mouthpiece. "I am going to blow up