Each of these four woodcut scenes represents an important alchemical concept . These would have been easily understood by adepts of the art. Saturn is represented by lead; Jupiter, by tin; Luna, or the Moon, by silver; and, the Sun, by gold and gold leaf. In each case men are working with the metals; melting, beating or engraving them. Illustration from 'Le Vray et Methodique Cours de la Physique Resolutive Vulgairement dite Chymie' ('The True and Methodical Course in Resolutive Physick, Commonly called Chemistry'), by Annibal Barlet, published in Paris in 1657. Although the book contains a great deal of alchemical jargon, it is for the most part good practical pharmaceutical chemistry.
© Science Museum / Science & Society Picture Library