The Methuselah Factor
by Vernon Eric Bridges
An environmental disaster is brought about by an American cargo plane blowing up its deadly cargo of biological weapons over England. Survivors set up a new community, guarded by wolfhounds. One of the settlers, Otto, invents an anti-gravity drive, enabling him to visit Mars. He discovers the remains of a once-flourishing civilisation and vows not to repeat the Martian errors of judgement.