John Allen (1670–1741) was a successful practitioner at Bridgewater, Somerset. He had a considerable reputation as a physician, and wrote a popular book, the 'Synopsis Universae Medicinae Practicae'. This book was first published in 1719 and ran to many editions in England and Europe in the early eighteenth century. The book combined the opinions of earlier physicians on almost all the diseases known at the time, as well as Allen’s own observations, concluding with ‘a curious treatise on all sorts of poisons’. Allen was a very practical man: he invented and patented a number of useful devices, including an engine designed to ‘raise water by fire’, and a steel-sprung carriage which greatly improved the speed and safety of passenger carriages.