What can one eighteenth-century Judaeo-Arabic medical manuscript reveal about language, knowledge, and scribal practice? In this book, you follow MS 1751, an extraordinary, little-studied volume from the Matenadaran, through its linguistic layers and textual transformations. You see how its orthography, morphology, and syntax shift across Arabic, Judaeo-Arabic, and Garshuni versions, and how these changes illuminate broader patterns of vernacular usage in the early modern Middle East. Drawing on unpublished material and detailed textual criticism, the book restores the earliest treatise in the manuscript and uncovers the networks that shaped its transmission. This study offers a rare, compelling window into medical writing and manuscript culture.