A second-century description by Aretaeus of Cappadocia divided headaches into three types: cephalalgia, cephalea, and heterocrania. Galen of Pergamon used the term hemicrania (half-head), from which the word migraine was eventually derived. He also proposed that the pain arose from the meninges and blood vessels of the head. Migraine was first divided into the two now used types – migraine with aura ("migraine ophthalmique") and migraine without aura ("migraine vulgaire") in 1887 by Louis Hyacinthe Thomas, a French Librarian. The mystical visions of Hildegard von Bingen, which she described as “reflections of the living light", are consistent with the visual aura experienced during migraines.