'Typus Arithmeticae', 1535.
© Science Museum / Science & Society Picture Library
Hand-coloured woodcut from the 'Arithmetic' section of the 'Margarita Philosophica' ('The Philosophical Pearl'), by Gregor Reisch (1467?-1525). First printed in 1503, this book was once considered the 'tree of all knowledge'. Divided into twelve 'books', it covers the topics of mathematics, cosmography, music, natural history, minerals, astronomy and medicine. This illustration shows arithmetic done using a pen and using counters.