Another area of great bibliographical interest to Klebs was medical herbals, especially incunabula herbals. Klebs’ collection of herbals, mostly dating from later than the fifteenth century, form the basis of the Library’s Herbals collection.
Klebs’ Bibliography of Incunabula Herbals, 1917
This is Klebs’ earliest bibliographical work on herbals. The entries are detailed compared to his later short-title catalog of incunabula of science and medicine.
A Klebs Incunabula Herbal, 1492
This book is a translation into Low German and enlargement of the Gart der Gesundheit of 1485, the first illustrated herbal to be printed. Klebs helped Harvey Cushing to obtain the Library’s copy of this 1485 incunable. The text includes 519 hand-colored woodcuts of plants, animals, and medical scenes.
"Herbal Facts and Thoughts," 1925
Klebs’ introduction, "Herbal Facts and Thoughts," is a study of the various editions of incunabula herbals, their authors, printers, typefaces, illustrations, relation to one another, and dates of publication. Incunabula do not have standard title pages as do later books, so dating them by other means becomes very important.