What is the X in X-mas?
version of the bicycle reinvented in the 1860s by the Michaux family of Paris. Its iron and wood construction and lack of springs earned it the nickname boneshaker. It was driven by pedaling cranks on the front axle. To increase the distance covered for each turn of the cranks, the front wheel was enlarged until, finally, in the ordinary, or penny-farthing, bicycle, the wheel would just go under the crotch of the rider. The penny-farthing nickname came from the smallest and largest British coins of the time, in reference to the disparity in the size of the wheels. By the second half of the 20th century, the original meaning was restricted to those knowledgeable in the history of the bicycle, while to others it referred to a children's tricycle, which duplicates the differentiated wheel size. The velocipede was eventually replaced by the more stable safety bicycle, having a chain-driven rear wheel