From The Styles of Eighteenth-Century Ballet by Edmund Fairfax (2003, 288-289):

Ever broken your nose while doing grands battements? A dancer in the eighteenth-century did:
“I have proven myself with these battements and have gone higher than the head. Indeed, I held up my left hand so that it was raised perpendicularly, and I touched the palm of my left hand with the right foot, or rather cou-de-pied, a clear indication of having disengaged the leg well. Take care, however, not to practice these battements violently; do them after you have made the sinews soft and flexible, and do not be heedless of keeping the foot on the floor well supported. In practicing these in a heat once, my beating foot displaced the other on the floor, and falling flat on my face, I broke my nose. With the same carelessness, Cesarini had the ill-luck to break an arm.” (Gennaro Magri. Trattato teorico-prattico di ballo. 1779. 1:40-41)