The Voynich "Roger Bacon" manuscript secrets--presumably magical or scien­tific and possibly containing a formula for an Elixir of Life--continue to defy deciphering efforts after almost four centuries, as this amazing history shows. Boughtabout the year 1586 by the Holy Roman Emperor Rudolph II, who had a keen interest in magic and sci­ence, the Voynich manuscript consists of some 200 pages, with many unusual anatomical, botanical, and astronomical illustrations. The work was thought to be that of Roger Bacon, the thirteenth-century English philosopher, who had a reputation for being a magician, and whom legend credited with discovery of an Elixir of Life. The writing, presumably in cipher, defied decipherment by Rudolph's scholars, and the manuscript passed in the eighteenth century from Prague to Rome, and in 1912 to America, when it was bought by Wilfrid Voynich, a rare-book dealer. In 1921, William R. Newbold claimed to have solved the cipher, but his claim was disputed by John M. Manly, who gave the manu­script the sobriquet "the most myste­rious manuscript in the world." In the 1960s the manuscript was acquired by the Beinecke Rare Book Library, and Robert S. Brumbaugh, a philosopher at Yale who had served in military intelligence during World War II, became interested in it, and began what has turned out to be a decade of effort to unlock the secrets of the cipher. In the course of his investi­gations Brumbaugh brought together a collection of essays tracing the manu­script's history, which form the basis of the present book. Brumbaugh himself in 1972 identi­fied the "alphabet" used in the cipher, and read plant and star labels, but the text has resisted application of the al­phabet. Efforts to transcribe and de­cipher the manuscript continue, and this book is a contribution to the efforts to reveal the secrets of medieval science, philosophy, and linguistics still locked in "the world's most mysterious manu­script."