A Trove of Zohars is an antic tale of investigative inquiry. Lawrence Weschler tracks down Stephen Berkman, the wet-collodion devotee who claims to have discovered the title trove, but it’s a long and loopy story. And indeed, Weschler’s account evolves into the fourth volume of his ongoing Chronicles of Slippage series, doing for the early history of photography and the long heritance of Judaism what the series’ first volume, the Pulitzer-shortlisted Mr. Wilson’s Cabinet of Wonder, once did for the history of museums and the phenomenology of marvel. And that’s only the half of it, for the main text sprouts a veritable delirium of digressive footnotes (taking up more than half the book), constituting what may be the closest we are going to ever get by way of memoir from this confounding and beloved writer.