“There once was a frog: A seventeenth century dried frog in ms. ROS 77.”

The article discusses an unpublished early modern Hebrew manuscript penned by the Italian Jewish physician Avraham Joel Conegliano (1665-1745) and today preserved at the Bibliotheca Rosenthaliana in Amsterdam. The codex includes two known medical excerpts, two Hebrew synonym lists, and a magico-medical compendium. Among its pages, the book conceals also several floral remains and even a desiccated frog, an unprecedented finding in the research fields of both Jewish magic and Hebrew manuscripts. The article offers an overview of the manuscript and its contents and presents relevant biographical information on the author, highlighting the cultural and intellectual milieu in which Jewish physicians were trained, operated and transmitted their knowledge in Northern Italy at the end of the seventeenth-century. The finding of organic material in the manuscript is discussed in light of Jewish and non-Jewish traditions on the manipulation of frogs for magico-medical purposes and it is interpreted as evidence that the manuscript was copied and used in the context of an active magico-medical tradition.