To Empedocle it also goes up again the doctrine of the four elements or rather earth, water, air and fire. He defines them the «four roots of all the things». Ippocrate applied him to the microcosm with his theory of the four humors, while Aristotle modified it in remarkable way in the IV century to.C. Egli brought back all the elements to a commune native subject, the proté hyle or First subject. The alchemists also defined it as «our chaos» or «dark mass», consequential from the fall of Lucifero and Adamo. To sublime it and to turn it into the pencil meant nientemeno that to bring the fallen Creation in misfortune to his native paradisiacal state. The principal appointment of every alchemist, its particular secret concealed behind fictitious appellatives, was that to find the essential subject to the conclusion of this work. Of other song, the enigmatic mottos sustain that simpler enterprise doesn't exist; in fact, the subject in matter would be present in every element, even in the dust of the road and what in reality it is the most precious thing of the world - as the Christ - to the ignorant person it seems «the most miserable of the terrestrial things». In base to the theories of Aristotle, the First subject associates to the four qualities of dry, cold, dampness and heat, and so it develops in the four elements. He retains that altering these four qualities is possible to also modify the elementary compositions of the substances to the purpose of trasmutarle. According to such conception, the job of the alchemist consists only in the «conversion (rotatio) of the elements»: «[...] The subject of the stone passes from a nature to the other, the elements they come little by little extracts and, to alternate phases, each imposes on the other [...] until all inclined ones they don't come downward, where they remain to lie». According to a law attributed to Pitagora, the number four define the ghost of all the terrestrial possibilities. II fifth Aristotelian element, the thin quintessence, finds only therefore in the superior sky of divine fire. Objective of the alchemists it was that to bring through it on the Earth repeated «rotations», to put aside that this happened distilling it spiritus or the alcohol, or imagining the divine light in the salt. To reach such purpose is necessary to go beyond the extreme outskirts of the inferior world the ring of Saturn, that separates the Earth from the Heaven. To overcome Saturn, that corresponds to Crono, god of the Greek weather, means to cross the border of the ephemeral linear time to cross the threshold of the golden time of the eternal youth in the divine circolarity. This dream would have had to be realized through the elixir of the eternal youth, or rather «the drinkable gold», whose notion had presumably come in Arabia from China and from India to the inizío of the medieval period. Already the more ancient alchemic document, from the programmatic title Physika kai Mystika (natural and secret Things) I'Opus Magnum divides in four phases, according to the different colorations: nero(nigredo), white (albedo), yellow (citrinitas) and red (rubedo). Irrelevant changes excepted, such division was unchanged for the whole history of the alchemy. Subsequently, further subdivisions were introduced, in strong contrast among them, you inspire to the number of the metal-planets or to the twelve stations of the zodiac listed in the following phases: 1. calcinatio: oxidation - Aries; 2. congelatio: cristalliz-zazione - Taurus; 3. fixatio: solidification - Gemini; 4. solutio: solution, fusion - Cancer; 5. digestio: digestion, division -Leo; 6. distillatio: separation of the solid from the liquid - Virgo; 7. sublimatio: sublimation - Libra; 8. separatio: separation -Scorpio; 9. ceratio: solidification in a state of wax- Sagittarius; l0. fermentatio: fermentation - Capricorn; 11. multipicatio: multiplication - Aquarius; 12. projectio: spolverizzazione of the pencil on the common metals - Pisceses. Such alchemic writing of the The-II century to.C. was published by a follower of Democrito and goner for a work of the teacher. The same Democrito brought back all the perceivable phenomenons to level sensoriale, also the colors, to the movement and the mutable constellations of lower case letters deprived particles of quality, that he defined atoms, «indivisible». According to the Greek philosopher, such atomic reality concealed behind a deceptive world of the appearances is incommensurably deep. A reconstruction of the history of the practical alchemy could start really with Democrito, mystical atomist and not alchemist, and he could end with the atomists not alchemists of the XX century that, to two hundred years from the negation of every scientific dignity to the hermetic art, and despite notable fruitless efforts, they have not succeeded in realizing through elementary trasmutasion, the fusion of the atomic nucleuses yet.