OTTO, Louis WILLIAM, 1754-1817; Count of •3losloy; b. in Baden, Germany; edu cated at Strasbourg; entered diplomatic service, and was an attache of the chevalier Luzerne in the French mission to the United States in 1779, first as secretary, and after went as charge d'afaires until 1792; married a daughter of the Livingston family; was employed by the committee of public safety in Paris in 1723 as a friend of the Girond ists, and when they fell was imprisoned until released by the overthrow of Robespierre; was afterward in diplomatic positions at Berlin, London, and Vienna, and negotiated the marriage of Napoleon I. with Maria Louisa in 1809. He died in Paris.
OTTO (or ATTAR) OF ROSES is the volatile oil or otto (see PERFUMERY) of the petals of some species of rose., obtained by distillation, ma highly prized as a perfmne. It is a nearly colorless or light yellow crystalline solid at temperatures below 80° F., lique fying a little above that temperature., It is imported from the e., where in Syria, Persia, India, and Turkey, roses are cultivated to a considerable extent for its sake. It is probable that the oriental Otto is the produce of more than one species of rose; and it is uncertain what species is cultivated in some'of the localities most celebrated for it ; but rosy Dainaseena is known to be so employed in the /1. of India, and a kind of otto is some times obtained by the makers of rose-water from rot centifolia in Blighted. See Rosie. Gliazipore, near Bemires, is celebrated for its rose gardens, which surround the town, and are in reality fields occupied by rows of low rose-bushes, which in the flowering seneon are red with blossoms in the morning, but the blossoms are all gathered before midday. Cashmere is noted for its extensive manufacture of Otto, as are also the neighborhoods of Shiraz and Damascus. 'l'o procure the Otto. the rose petals are usually distilled with about twice their weight of water, and the produce exposed to the cool night-air in open vessels, from which the thin film of Otto is shimmed with a feather in the morning. Twenty thousand flowers are required to yield Otto equal to the weight of which even in India is worth about 100 rupees, or £10 sterling. Otto is said to have been first procured by what may be celled an accidental distillation of rose-petals exposed with water to the heat of the sun, and to have been found floating on the surface of the water; and it is still sometimes obtained in India by such a process. It: is said to be also obtained by dry distillation of rose-petals at a low temperature. During the distil
lation of rose-petals, a small quantity of a solid volatile oil comes over (solid oil of rores, see below), which crystallizes and floats on the water in the receiver, and, which is sometimes called English oil of roses. Otto of roses is not unfrequently adulterated with sandal-wood oil, oil of rhodium, etc. It is much used for making Lair-oil, a drop (AIL being enough to impart a pleasant odor to a considerable quantity. It is also used in making lavender-water and other perfumes. The odor of otto itself is too power ful to he altogether plensant. Another method of obtaining the :cent of roses is describcd in the article PERFUMERY. Otto of roses is a mixture of two 'volatile or essential oils; the one solid at ordinary temperatures, and the other liquid. The solid oil of ro,,s (rose camphor. stietroptfme of oil of roses) exists separately in crystalline plates. melts; or fuses at 203? F., and boilst at about 592°. It possesses of itself very little odor, is insoluble in alcohol, but soluble in ether. It is composed of carbon and hydrogen, The liquid oil of roses (eleoptime of oil of roses) is a very fragrant liquid, to which the veto of roses is indebted for its delicious perfume, and appears to consist of carbon, hydroeen, and oxygen; though its composition and properties have not been attentively studied. 79ae otto of roses may be regarded as a solution of one part of the solid oil in two parts of the liquid. To separate these oils, the Otto is frozen at a temperature below 80' F., and the congealed mess pressed between folds of blotting-paper, which absorbs the liquid oil of roses, and leaves the solid. Another process which may be resorted to is to treat the frozen otto with alcohol, which dissolves the liquid oil, and leaves beltintl the solid. The eat° of roses has a specific gravity of 802, water being 1000; it is combustible; mind when its vapor is diffused through oxygen. and set fire to, a violent explosion takes place: 1000 parts of alcohol dissolve 7 parts of the otto in the cold, and 33 parts when slightly heated. 'Flue principal use to which Otto of roses is put is as a perfume. Milk of roses and lavender-water owe their fragrance to the presence of the otto. A good receipt for oil for the hair is olive oil, colored by alkanet, and scented by a few drops bf otto, and this is very generally sold under the name of otto of roses. _Medicines arc occasionally perfumed by otto of roses, and it is sometimes added to unguents and spirit-washes.