A faulty part changes a calibration device into a time machine that takes dropout student Matt Fuller further and further into the future including a theocracy of 2252 (where Martha, a sexually spontaneous vestal virgin, joins the adventure) and an AI-tocracy some 24,000 years later.
So he had to plan. The next time he pushed the button—if the simple linear relationship held true—the thing would be gone for over three days. Next time, over a month; then over a year. Then fifteen years, and way into the future after that.

Variants

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  1. The Accidental Time Machine by Joe Haldeman (Ace Books, August 2007).
    2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . written by Joe Haldeman