FIRENZE, BIBLIOTHECA MEDICEA LAURENZIANA, MS. PLUT 74.17, C. 75R; BY PERMISSION OF MIBAC

OVERWRITING GENESIS. A medieval codex book (Plut. 74.17) includes numerous pages made of even older Torah scrolls. Reused to write down medical and pharmaceutical treatises in Greek, those Hebrew scroll sheets originally contained sections of the books of Genesis and Exodus, a portion of the former still vaguely visible on this photo. Such rewritten manuscripts are called palimpsests, and they were made by erasing or scraping the older text and overwriting it with a new one. Thanks to advances in digital imaging, these “undertexts” can still be read.