_Petitgrain oil_, obtained by distillation of the twigs and unripe fruit of Citrus bigaradia. There are two varieties of the oil, the French and the South American, the former being the more valuable. Specific gravity at 15 deg. C., 0.886-0.900; optical rotation, -3 deg. to +6 deg.; refractive index at 20 deg. C., 1.4604-1.4650; esters, calculated as linalyl acetate, 40-55 per cent., for the best qualities usually above 50 per cent.; soluble as a rule in 2-3 volumes of 70 per cent. alcohol, but occasionally requires 1-2 volumes of 80 per cent. alcohol. Among its constituents are limonene, linalyl acetate, geraniol and geranyl acetate. _Pimento oil_ (allspice), distilled from the fruit of Pimenta officinalis, which is found in the West Indies and Central America. Specific gravity at 15 deg. C., 1.040-1.060; optical rotation, slightly laevo-rotatory up to -4 deg.; refractive index at 20 deg. C., 1.529-1.536; phenols, estimated by absorption with 5 per cent. potash solution, 68-86 per cent.; soluble in 1-2 volumes of 70 per cent. alcohol. The oil contains eugenol, methyl eugenol, cineol, phellandrene, and caryophyllene. _Rose oil (otto of rose)_, distilled from the flowers of Rosa damascena, though occasionally the white roses (Rosa alba) are employed. The principal rose-growing district is in Bulgaria, but a small quantity of rose oil is prepared from roses grown in Anatolia, Asia Minor. An opinion as to the purity of otto of rose can only be arrived at after a very full chemical analysis, supplemented by critical examination of its odour by an expert. The following figures, however, will be found to include most oils which can be regarded as genuine. Specific gravity at 30 deg. C., 0.850-0.858; optical rotation at 30 deg. C., -1 deg. 30' to -3 deg.; refractive index at 20 deg. C., 1.4600-1.4645; saponification value, 7-11; solidifying point, 19-22 deg. C.; iodine number, 187-194; stearopten content, 14-20 per cent.; melting point of stearopten, about 32 deg. C. A large number of constituents have been isolated from otto of rose, many of which are, however, only present in very small quantities. The most important are geraniol, citronellol, phenyl ethyl alcohol, together with nerol, linalol, citral, nonylic aldehyde, eugenol, a sesquiterpene alcohol, and the paraffin stearopten. _Rosemary oil_, distilled from the herb Rosemarinus officinalis, and obtained from France, Dalmatia, and Spain. The herb is also grown in England, but the oil distilled therefrom is rarely met with in commerce. The properties of the oils vary with their source, and also with the parts of the plant distilled, distillation of the stalks as well as the leaves tending to reduce the specific gravity and borneol content, and increase the proportion of the laevo-rotatory constituent (laevo-pinene). The following figures may be taken as limits for pure oils:--