The Sibbald Library holds some 38 editions of the De medicina of Celsus, not counting those in which his works are included in collections by several authors. These include two French, one Italian and two English translations of the Latin text from the 18th and 19th centuries. From the 20th century there are two editions of the three volume Loeb edition with an English translation. But, useful as these are, of much more interest are our two editions from the 15th century: one is a Venetian edition of 1497, the other is the editio princeps-the first printed text of the workpublished in Florence in 1478, 1 which I shall consider here. This book is the first complete textbook of medicine to be printed and has some claim to be the oldest extant text on the whole of medicine; certainly it is the first complete account of medicine that was originally written in Latin for all that much of its material comes from earlier Greek sources. It is also the earliest surviving encyclopaedic Latin medical text by a single author. The number of editions-there were 49 printed editions between 1478 and 1841 2-is one indication of the importance attached to the work, as is the number of times that Celsus's opinions are quoted by later authors. In this first part, I shall consider Celsus and the text of the first edition leaving description of our copy of the book to the second part. The author De A. Cornelii Celsi gente patria uita nihil traditum esse apud ueteres notum est. 3 'Nothing about the race, nationality or life of Aulus Cornelius Celsus was recorded to be passed down by the ancient writers.' 3 Thus begins Marx's account of what remains of the single surviving work of Celsus, his eight books on medicine which came to be known under the title of De medicina.