The geometry of fencing

In 1628, Girard Thibault wrote Académie de l’Espée, a rapier manual based on mathematical foundations. Science historian Daniel Margocsy of Slate offers a feature article on the fencing tome. (photos)

From the article:

Girard Thibault’s Académie de l’Espée (1628) puts the art of wielding the sword on mathematical foundations. For Thibault, a Dutch fencing master from the early seventeenth century, geometrical rules determined each and every aspect of fencing. For example, the length of your rapier's blade should never exceed the distance between your feet and the navel, and your movements in a fight should always be along the lines of a circle whose diameter is equal to your height.