('Book of Secrets'), Abu Bakr al-Razi may have created sulfuric acid without being aware of it:Take white (Yemeni) alum, dissolve it and purify it by filtration. Then distil (green ?) vitriol with copper-green (the acetate), and mix (the distillate) with the filtered solution of the purified alum, afterwards let it solidify (or crystallise) in the glass beaker. You will get the best qalqadis (white alum) that may be had. In an anonymous Latin work variously attributed to Aristotle (under the title , 'Book of Aristotle'), to Abu Bakr al-Razi (under the title , 'Great Light of Lights'), or to Ibn Sina, the author speaks of an 'oil' () obtained through the distillation of iron(II) sulfate (green vitriol), which was likely 'oil of vitriol' or sulfuric acid. The work refers multiple times to Jabir ibn Hayyan's Book of Seventy (), one of the few Arabic Jabir works that were translated into Latin. The author of the version attributed to al-Razi also refers to the as his own work, showing that he erroneously believed the to be a work by al-Razi. There are several indications that the anonymous work was an original composition in Latin, although according to one manuscript it was translated by a certain Raymond of Marseilles, meaning that it may also have been a translation from the Arabic. According to Ahmad Y. al-Hassan, three recipes for sulfuric acid occur in an anonymous Karshuni manuscript containing a compilation taken from several authors and dating from before . One of them runs as follows: The water of vitriol and sulphur which is used to irrigate the drugs: yellow vitriol three parts, yellow sulphur one part, grind them and distil them in the manner of rose-water. A recipe for the preparation of sulfuric acid is mentioned in , an Arabic treatise falsely attributed to the Shi'i Imam Ja'far al-Sadiq (died 765). Julius Ruska dated this treatise to the 13th century, but according to Ahmad Y. al-Hassan it likely dates from an earlier period: Then distil green vitriol in a cucurbit and alembic, using medium fire; take what you obtain from the distillate, and you will find it clear with a greenish tint. Sulfuric acid was called 'oil of vitriol' by medieval European alchemists because it was prepared by roasting iron(II) sulfate or green vitriol in an iron retort. The first allusions to it in works that are definitely European in origin appear