Put a lump of sal ammoniac in a heated vessel and, after a time, a white crust grows on the cool upper wall, as if the solid had climbed the glass by itself. This is sublimation: a solid rising as vapor, and settling again as a solid, without a visible liquid stage in between. Alchemists watched it with wonder for centuries, and in the Compound of Alchymy the English writer George Ripley made it the eighth of his twelve gates. Ripley and His Twelve Gates George Ripley lived in the fifteenth century, and he is remembered as an Augustinian canon of Bridlington in Yorkshire, who studied abroad and returned to England. He wrote his Compound of Alchymy in verse and dedicated it to King Edward IV in 1471. The book lays out the Great Work as a castle with twelve gates, each of which the alchemist must pass. The text circulated in manuscript, and it was printed later, notably in Elias Ashmole's Theatrum Chemicum Britannicum in 1652. The usual order of the gates is Calcination, Sol...

Every parent knows that you cannot feed a newborn all at once. The food must come in small amounts, at the right temperature, again and again, and a hurried hand can do more harm than hunger. The alchemists took this ordinary lesson and gave it a place in their art. In the seventh of George Ripley's Twelve Gates, called Cibation, the matter of the work is treated like a living infant, and the practitioner is told to feed it with patience. The Word and the Gate "Cibation" comes from the Latin cibus , food, and means feeding. In the alchemical tradition it was one of the standard operations, and many authors list it among the stages of the work. Ripley, the fifteenth-century English canon who wrote The Compound of Alchemy in 1471, makes it the seventh of twelve gates, after congelation and before sublimation. The order of the gates is part of the teaching. By the time the matter reaches Cibation, it has been purified, joined and made solid. It is a fragile thing, new...

A man in a cap and plain work clothes stands at a large hearth, holding a long flat paddle over a bright fire. On a stone block beside him sits a wide basin filled with small round pieces. In the lower right corner, an animal crouches on the floor, and through an open window a person walks past a church. This is the eighteenth emblem of Michael Maier's Atalanta Fugiens, and its motto plays on two words, fire and gold: fire loves to ignite, not to gild, but to make gold. The book was printed in 1617 at Oppenheim. It has fifty emblems, and each one joins an engraving, a Latin verse, a prose discourse and a fugue for three voices. The engravings are attributed to the workshop of Matthäus Merian. Maier, a physician at the court of Emperor Rudolf II, knew the furnace room well. The Motto The Latin line is dense, and translators have rendered it in different ways. Its sense seems to be that fire is for kindling and that its true product is gold itself, and not gold on the surface. ...

Put a pot of wine on a fire and cover it with a cap shaped like a bell, and something remarkable happens. The wine boils, its vapor climbs into the cap, cools on the walls and runs down a narrow spout into a waiting flask. What drips out is clear, sharp and strong, and it is not the same as what went in. The alembic is the tool that made this possible, and it has been, for a thousand years and more, the alchemist's most faithful companion and one of the most vivid symbols of refinement. A Word With a Journey The word alembic comes from the Arabic al-anbiq , which itself comes from the Greek ambix , a cup or a cap. It describes in particular the upper part of a still, the head that catches the vapor. In English the word later came to mean the whole apparatus. The route of the word follows the route of the craft, from Greek Egypt through Arabic science to medieval Europe. The earliest known distilling equipment appears in the writings of the Greek-speaking alchemists of Roman ...