Our children expect peculiar vacations. While their friends go to Disney World or the beach, we go to monasteries and rare book libraries, making a holiday out of castles and forests along the way and returning with odd bits of nature or history for our display case. Here, from a gravel driveway in the Cotswolds, is a fragment that might be a Neolithic arrowhead, and here, from a glade in one of Scotland’s oldest forests, is just the sort of flat stone you’d find in a fairy kitchen. Now that we’re back, the luster of our souvenirs is fading; they’re beginning to look like ordinary rocks. Yet they remind us of something ineffably precious, for they represent, at the very least, a universal longing to find renewal by re-creating the good things of the past.