Raymond Clemens, the Beinecke’s curator of early books and manuscripts, said that while many book dismantlers operated covertly, Mr. Ege “was very open and blunt” about the technique being potentially useful to scholars.

Mr. Ege’s family had long stored boxfuls of material. Yale’s purchase, for an undisclosed price, also includes covers for disassembled books, which may bear markings from monastic scribes and past owners. The library staff will be digitizing the material and looking for related pages. Yale has scheduled a conference on broken books for 2018.

Lisa Fagin Davis, the executive director of the Medieval Academy of America, said she “can’t wait” to pore over the Ege documents. She is part of a curatorial team organizing a group of exhibitions focusing on medieval books and fragments acquired by collectors in the Boston area. It will be set up next year at three sites in Boston and Cambridge.

She has also set out to digitally reassemble the Beauvais Missal, a 13th-century French prayer book. In the 1940s, dealers including Mr. Ege dispersed its 309 pages, and Dr. Davis has tracked down a third of them. (On Thursday, in an online Christie’s auction, a Beauvais Missal sheet and a 12th-century page from a German or Austrian prayer book that Mr. Ege handled sold for a few thousand dollars each.)

Dr. Davis added in an email, “It’s a very exciting time to be a ‘fragmentologist.’ ”

Christoph Flüeler, a professor at the University of Fribourg in Switzerland, is overseeing a new centralized database, the Fragmentarium, for pieces of medieval manuscripts. More than a dozen institutions are collaborating, including Harvard, Yale, Stanford, the British Library and the Vatican. Dr. Flüeler said that historians, dealers and collectors would eventually be able to upload images of fragments and perhaps determine the original contexts.