At some point in their studies, the friars noticed that rose petals were resistant to certain pests, and concluded that distilling the petals would create a disinfectant that could prevent humans from catching the bubonic plague. “It didn’t work at all,” Foà says, “but by 1380, they had created this rosewater tonic, which is still one of our bestsellers.” Today, the company’s rosewater products based on this original recipe are sold as skin toner.I guess innovation can't always be planned.