“We do not allow anyone to see it, let alone photograph it,” the director of Vienna’s Federal Museum of Pathology at the Narrenturm—the Tower of Fools—told Lena Herzog when she first attempted to visit. The Narrenturm, built in 1784, is also called the Madhouse Tower, so named because it was Austria’s first psychiatric hospital. But what drew Herzog to its door was its collection of what eighteenth-century monks in her native Russia called “lost souls,” and what nineteenth-century doctors described as “incompatible with life”—unborn fetuses and newborn infants who, by virtue of nature’s mutations, were unable to survive but who were preserved by early modern collectors as objects of scientific inquiry and private wonder. These human and animal specimens were often displayed next to maps of the earth and of stars—evidence of a desire to define boundaries and map the unknown. Herzog has photographed a dozen of these extraordinary collections, including Tsar Peter’s Kunstkammer in St…