When John Napier published his invention of logarithms in 1614 he was announcing one of the greatest advances in the history of mathematics, and log tables were used universally until the mid 1970s. With his Rabdologia, an ingenious calculating tool composed of numbered rods which came to be known as 'Napier's Bones', he enabled people in the marketplace to do multiplication sums without knowing any multiplication tables. Perhaps the most extraordinary thing about this most extrordinary man was that his great inventions were made without the stimulus of talking to other mathematicians in mainstream Europe. Working away in comparative isolation in a tower house in Scotland, Napier produced methods of calculation that literally changed lives all over the world. He is the father of the slide-rule and the grandfather of today's calculators. Despite his achievements, he remains curiously uncelebrated, and this absorbing story of his life aims to give John Napier his true status. This new edition has been redesigned in a new format and has a new cover.