No. 9. Rupescissa - The book of QuintessenceJohn de Rupescissa's (John of Roquetaillade) key work on distillation and the quintessence was written about 1360 a century before the invention of printing. It circulated widely in manuscripts copied from one alchemist to another. Because of this there were many different variations of the text. All the versions, however, discuss the making of the quintessence of wine, of preparing a quintessence of gold and demonstrating the diseases and conditions it could help alleviate.
Rupescissa, a Franciscan monk, was imprisoned by the Pope, not for his alchemical writings but for his prophecies and denunciations of ecclesiastical abuses. These prophecies were quickly forgotten, but his clear and practical indications on alchemical distilling were very influencial on later generations of alchemists. His Liber de consideratione quintae essentiae was one of the most important early writings of European alchemy.
This English translation was adapted by Adam McLean from an early 15th century translation contained in The British Library MS Sloane 73. The language has been extensively modernised and revised, to make it readable by people unable to steer their way through Middle English.