This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
Attar of roses (also called "otto,"- in French essence de rose) is the rose oil of commerce. It is produced on a large scale in the Turkish province of Roumelia, and principally on the warm southern slopes of the Balkans. The same article is also made in Tunis, India, Persia, and the south of France, but the quantity produced is small and the price so high that very little is exported. The Roumelian attar is made from the Rosa damascena by distillation. The color of this rose is generally red, though sometimes white, and blooms in May and June. The flowers are on trees that average about six feet high, which are not only planted in rows, but are tended zealously from autumn till midsummer. The flowers when in full bloom are plucked before sunrise, sometimes with, sometimes without the calyx, but only in such quantities as can be distilled on the day that they are plucked. The still is a plain tinned apparatus, from which a long curved tube is directed through a tub of water, and into a large bottle. The still stands on a. stone hearth, and usually in the shade of trees near a running stream. The firing is done by wood. The still holds from twenty-five to fty pounds of roses, which are covered with twice that quantity of water and boiled half an hour. The distilled liquid that passes over into the bottle is allowed to stand, when the attar rises on the surface, and is skimmed off, the water ultimately being sold as rose water at Constantinople. The attar is kept in copper cans and the rose water in bottles. A rose tree is at its best in its fourth year, an acre of four-year-old trees producing from one to two tons of flowers, about 16,000 well-grown roses being required to produce one ounce of oil of rose, or 3,000 pounds to yield one pound. Much depends on the spring weather, as rains and frosts illy affect the bloom. The Kyzanlik (Roumelia) oil of rose is considered the best; however, the oil from Kaschmire in Persia is the most excellent one.
Oil of rose is very permanent. Specific gravity about 0.860, but it may vary between 0.840 and 0.890. It boils at 222° C. The odorous portion is quite freely soluble in alcohol, while the inodorous stearopten is sparingly soluble in this liquid; absolute alcohol yields with the oil a clear solution. The oil has the odor of the flowers in a high degree, and when suitably diluted with alcohol is very fragrant.
Rosewood Oil, formerly the chief adulterant of oil of rose, out now replaced by the cheaper oil of rose-geranium, is obtained by distillation from the wood and roots of the tree convolvulus scoparius and floridus L,. has a rose-like odor, and boils at 249° C.