From a distance, Eugène Atget’s photograph Environs, Amiens (circa 1897) appears to be an abstraction. It resolves as you approach into something like a craggy mountain peak or a mound of snow-covered rocks, but you have to get up close before the spotted triangular form in an ivory expanse comes into focus as a flock of birds perched atop the shingled roof of what must be a dovecote. One pokes its head out of a hole in the little door beneath the eaves. The tightly cropped picture, shot from below at a neck-straining angle, frames the building in perhaps the least intuitive way imaginable. Even Atget’s more familiar pictures of the deserted streets and shabby interiors of old Paris still breathe mystery a century after his death. They are blissfully unburdened by ideas or narratives or even a discernible style.…