Sulfuric acid the Hellenistic alchemical works of Zosimos of Panopolis, in the treatise "Phisica et Mystica", and the Leyden papyrus X. Medieval Islamic era alchemists, Jābir ibn Hayyān (c. 721 – c. 815 AD, also known as Geber), Razi (865 – 925 AD), and Jamal Din al-Watwat (d. 1318, wrote the book "Mabāhij al-fikar wa-manāhij al-'ibar"), included vitriol in their mineral classification lists. Ibn Sina focused on its medical uses and different varieties of vitriol. Sulfuric acid was called "oil of vitriol" by medieval European alchemists because it was prepared by roasting "green vitriol" (iron(II) sulfate) in an iron retort. There are
Today Is Yesterday Today Is Yesterday Today Is Yesterday is a 2002 compilation album by English folk/rock singer-songwriter Roy Harper. Amongst its 17 tracks are six unreleased and eight rare songs. All the tracks were recorded between 1964 and 1969. Tracks 1–9 date from 1964–1965 and were recorded on an old mono Ferrograph quarter-inch Reel-to-reel audio tape deck. These tracks formed a demo tape that landed Harper his first record contract. Track 10 is a re-recording of a part of that demo tape and became the B-side of Harper's first single. Tracks 11 and 13 became Harper's second single, while track 12 was