The earliest machine propelled by cranks and pedals with connecting rods was built in 1839-40 by Kirkpatrick Macmillan (1810-78) of Dumfries, Scotland. A copy of the machine is now in the Science Museum, London, England.Italian artist and scientist Leonardo da Vinci (1452-1519) is often credited with designing the first 'bicycle', having drawn a machine propelled with cranks and pedals in the 1490s. Macmillan was the first person known to have constructed such a machine, but this was not followed up. Four-wheeled bicycles were produced successfully for 20 years in England by Willard Sawyer from 1845. However it was French coachbuilder and wheelwright Pierre Michaux who started producing the first machines to be recognized as bicycles, in March 1861. Michaux created the first Velocipede by fitting a crank and pedals to the front wheel of a 'hobby horse' that had been brought to him for repairs (a hobby horse was a wooden framed machine powered by the rider 'running' whilst seated on the saddle). Their popularity boomed: by the end of the 1860s there were around 60 velocipede builders in Paris and 15 more in the French provinces. By 1970, the 'Compagnie Parisienne des Velocipedes' – formerly Michaux's business, but since taken over by the Olivier brothers - employed 500 workers and produced 200 machines a day.