In 1884 J. McCammon patented this design of chain-driven bicycle which represents one of the earliest pedal-operated bicycles to have a drop frame suitable for a lady. to ride with comfort and decorum. The general configuration of McCammon’s bicycle anticipated the Rover ‘safety’ bicycle of 1885 but differed in having a frame consisting of a single curved tube bent downwards between the two wheels. The front wheel is smaller in diameter than the rear wheel, while the front fork is slightly raked and at the end, at the bearings, turned rearwards. The steering joint is on two lugs behind the head tube. The sprung leather saddle is mounted on an adjustable pillar located on the upright portion of the frame. The pedal crank is carried in a forked frame hinged at the bottom of the main tube which permits the driving chain to be adjusted to the required tension – possibly the earliest known method for adjusting in a simple way the tension on a bicycle chain. The length of the pedal crank may be adjusted to suit the rider. McCammon’s 1884 bicycle incorporated various design features advanced for the period of its construction and was possibly the first bicycle to be sold complete with mudguards. The front wheel is 22 inches (56 cm) in diameter, the rear 38 (97 cm) inches, and both have direct spokes, ball-bearing hubs and solid rubber tyres. The wheel base is 40 inches (1 m) and the complete bicycle weighs 49lb (22 Kg).