Wherein I discover my aptitude as a hitchhiker, meet another guy named Peter Moore (but decline to buy him a cocoa), and learn how to spell “dirndl.” THE SUMMER BEFORE I LEFT FOR PARIS, my dad fished an antiquated map of Europe from his shoebox of National Geographic treasures, and vouchsafed it to his wandering son. He did the same, a few years later, when I was traveling with friends in central Africa, and it was, alarmingly…