The High-Wheel Bicycle

In 1870 the first all metal machine appeared. (Previous to this metallurgy was not advanced enough to provide metal which was strong enough to make small, light parts out of.) The pedals were still attached directly to the front wheel with no freewheeling mechanism. Solid rubber tyres and the long spokes of the large front wheel provided a much smoother ride than its predecessor. The front wheels became larger and larger as makers realised that the larger the wheel, the farther you could travel with one rotation of the pedals. You would purchase a wheel as large as your leg length would allow. This machine was the famous 'Penny Farthing'. The bicycles enjoyed a great popularity among young men of means (they cost an average worker six month's pay), with the heyday being the decade of the 1880's.
Because the rider sat so high above the centre of gravity, if the front wheel was stopped by a stone or rut in the road, or the sudden emergence of a dog, the entire apparatus rotated forward on its front axle, and the rider, with his legs trapped under the handlebars, was dropped unceremoniously on his head !.
The High Wheel Tricycle

While the men were risking their necks on the high wheels, ladies, confined to their long skirts and corsets, could take a spin around the park on an adult tricycle. These machines also afforded more dignity to gentlemen such as doctors and clergymen. Many mechanical innovations now associated with the automobile were originally invented for tricycles. Rack and pinion steering, the differential, and band brakes, to name a few!