Popular Science, joulukuu 1878
The practice of dyeing the hair is very much in use among the Persians, who mostly employ the plant henna for this purpose. According to Dr. Tholozan, the private physician of the shah, the powdered leaves of the plant are made into a paste with hot water and then applied to the head, the hair, and the nails. This is done in a vapor-bath. This first application lasts an hour and a half to two hours, and then the parts are freely washed in water. The henna gives an orange-red color, very beautiful on a white beard, so that many old men use it. To change the reddish color of hair into a fine, lustrous black, the parts are coated, at the same sitting, with a paste formed of another powder - that from the leaves of a kind of indigo-tree cultivated in Persia. This is called reng; it remains applied about two hours. The henna gives different colors according as it acts on white, fair, or dark hair. It alters very quickly in moisture, and loses its properties in long sea-voyages. Experience seems to have proved that it gives suppleness to hair, but it causes it to whiten prematurely. Fair-haired people in Persia always color their hair black, but the black is not so intense as that produced in persons of dark complexion. Skin reddened and blackened with the two pastes soon regains its natural color on being washed with soap and rubbed with the fingers, whereas the dye adheres firmly to the hair, which it penetrates. Reng is sometimes used alone, and gives a blue-violet color.