Distillation is a very old technique, probably of Mesopotamian origin and was developed by the Egyptians and made perfect in the Middle Ages by the Arabs. It uses the principle that the major part of the odorous molecules closed in a flower, or a resin can be transported with vapour. In a cauldron (alambicco) the substances to be distilled are mixed with a quantity of water equal to five times their weight. The liquid is brought to boiling point  when it is transformed into vapour which passes  through the odorous substances and is filled with essential oils. The “odorous vapour” passes through the swan neck into a cooling area (a long swan neck immersed in a cold water container) condenses and drips into the decanting vase. Due to a difference in density the essential oil is separated from the water (which remains perfumed and is also used) is gathered. Today’s method integrates this procedure with a subsequent phase called fractioned distillation, which eliminates different substances thereby increasing the intensity and persistence of the essences. The elimination of terpenes and the separation of the resins improves the stability and the preservation of the essences.