Scotsman John Napier is best known to for his treatise on Protestant religion. However, it was his interest in a completely different subject that radically altered the course of mathematics. After forty years of dabbling in maths, he revealed his table of logarithms in the early 17th century. This study unit is just one of many that can be found on LearningSpace, part of OpenLearn, a collection of open educational resources from The Open University. Published in ePub 2.0.1 format, some feature such as audio, video and linked PDF are not supported by all ePub readers.