“Compound interest was once regarded as the worst kind of usury and was severely condemned by Roman law and the common laws of many other countries. Richard Witt’s book Arithmeticall Questions, published in 1613, was a landmark in the history of compound interest. It was wholly devoted to the subject, whereas previous writers had usually treated compound interest briefly in just one chapter in a mathematical textbook. ... Witt was a London mathematical practitioner and his book is notable for its clarity of expression, depth of insight and accuracy of calculation, with 124 worked examples.”