IMAGES PLACE US in time, gluing unremarkable and historically urgent moments in a fixed setting or context, but mostly they thrill our senses in other varied ways. They challenge us with questions and ferry nostalgia. Images set our faces electric at the sight of something truly wonderful. The primary function of a photograph is not measurement, but there are those that suggest it all the same. Those images, thornier in intent and unwedded to a single place, become a kind of cloverleaf—of circumstances, of timelines and beliefs, of people.