Arnica:
Otherwise known as Mountain tobacco or Leopard's bane, Arnica was formerly in the the official Pharmacopea's of both Britain and the US. It has always been used externally, usually as a cream, on unbroken skin because of it's toxicity, to treat sprains, bruises, and chilblains. The plant is poisonous if taken internally except in homeopathic doses, and I honestly wish now that I'd prepared dinner for the hated Gerald using Arnica on those horrible long winter nights when he used to inflict his presence on me on the pretext of familial devotion, whilst eyeing up my family jewels.
