One of my Jeeps gets used for challenging my skills. Negotiating a steep ravine can be adrenaline pumping at 4 mph. When I was out in Colorado, I took the "road" over Hurricane Pass -- white knuckle when you get to the part where the trail is a narrow two-track with mountain on one side and lots of open air on the other. Met a vehicle coming the other way, my wife had to stick her head out the window to let me know how close my tires were to the cliff.
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-- FORTRAN manual for Xerox Computers --