Until the nineteenth century, Leonardo da Vinci was generally known only as a painter. Little or nothing of his sculpture or engineering works survived, and his notebooks, the only surviving evidence of his insatiable curiosity and fertile mind regarding science and technology, were long hidden away, dispersed in private hands. It was only after 1800 that the record of his intellectual and technical accomplishments, the thousands of pages of writings and drawings that we collectively refer to today as Leonardo’s codices, began to surface, be studied, and published.