Other Artemisia-oils are described under Tarragon, Wormseed, and Wormwood (pp. 1431, 1432).
Mustard oil.—Besides the fatty oil obtained from mustard (see p. 1396), a volatile oil is pro duced (it does not pre-exist), by distilling macerated brown mustard-seed with water, which is added at a temperature not exceeding 50° (122° F.). The oil is colourless or yellowish, of intensely penetrating odour and flavour of mustard, sp. gr. boils at 148° (298° F.), dissolves slightly in water, readily in alcohol and ether, and in 3 times its weight of cold sulphuric acid at 168° Tw.
Myrrh-oil.—When myrrh (see Resinous Substances—Myrrh), is distilled with water, 100 lb. will yield about 8 oz. of thickish, pale-yellow essential oil, having an odour and flavour of myrrh.
Myrtle-oil.—The leaves, flowers, and fresh fruits of the myrtle (Myrtus communis), by aqueous distillation (iu September), yield a yellowish or greenish-yellow oil, of great fragrance, about 5 oz. being obtained from 1 cwt. of leaves. Perfumers mostly replace it by an artificial compound.
Nasturtium-oil.—The seeds of Nasturtium officinale, under distillation, give an oil boiling at 120°-280° (248°-536° F.).
Neroli-oil.—Tbe fresh flowers of the bitter orange (see Fruit—Oranges, p. 1025), by aqueous distillation, yield per cent. of essential oil, the extraction of which is carried on chiefly at Grasse, Cannes, and Nice, in S. France ; also in Algeria. The finest trees afford about 30 kilo. of flowers. The oil is commonly adulterated with bergamot and petit-grain (qq. v.), -1 of the former and * of the latter being added to * of true neroli. The yield from 1 ton of flowers is about 40 oz., worth 20/., the residuary water, known as " orange-flower water," or aqua Napha, is worth en additional 10/. The flowers of the sweet orange yield less than half the amount of oil ; those of the shaddock (p. 1026) make a very good neroli. Pure neroli-oil is brownish, of most fragrant odour, bitterish aromatic flavour, sp. gr. at 11° (52° F.). It is very largely used in perfumery.
Other oils from the Citrus genus are described under Bergamot, Cedrat, Lemon, Orange, and Petit-grain (pp. 1417, 1419, 1423, 1425, 1427).
Olibanum-oil.—When olibanum (see Resinous Substances—Olibanum) is subjected to aqueous distillation, it affords a thin, yellowish oil, of pleasant turpentinous odour, sp. gr. and boiling at 162° (323° F.).
Orange-oil.—The scarcely-ripe fruit of both the sweet and bitter variety of orange (see p. 1025) is made to yield an oil from the rind, by means of the " sponge " or the geuelle process (see p. 1457), which is largely produced at Messina and in S. France. That obtained from the sweet orange is termed essence de Portugal ; that from the bitter, essence de bigarade ; the latter is much the more valuable. Both are used in liqueur-making and perfumery.
Other Citrus-oils are described under Bergamot, Cedrat, Lemon, Neroli, and Petit-grain (pp. 1417, 1419, 1423, 1425, 1427).
Orris-oil.—Orris-root (see Perfumes—Orris-root), dried, and then subjected to aqueous distil lation, affords an exceedingly minute quantity (about per cent.) of volatile oil, not to be found in the living root.
Parsley-oil.—The fruits of the parsley (Coruna Petroselinum), distilled with water, afford a thin essential oil, greenish-yellow when fresh, colourless when rectified, with an odour of the fruit, sp. gr. .04, solidifies at 2°-8° (35*°-46*° F.), boils at 160°-170° (320°-338° F.), and dissolves readily in alcohol. At Grasse (S. France), the yield is 1 lb. of oil from 250-300 lb.
Patchouly-oil.—An essential oil is extracted from patchouly or pucha-pat (Pogostemon Patchouly [Plectranthus crassifolius]), a native of Silhet, Province Wellesley, Singapore, various islands in the E. Archipelago, and Java. There are two kinds, known as toun-tileim or tildm-outan, and tildm-wangi ; the former is the common and less fragrant, the latter is the cultivated and more admired. Fisher, of Singapore, who produces about f of all the patchouly-oil of commerce, proceeds as follows :—The plants are grown in rows 4-5 ft. apart, in stiffish clay containing a small per centage of silica. They are raised from cuttings struck iu the open, and sheltered from the sun by c000-nut shells till rooted. The gathering is done in fine weather and after the dew is off; the tops and green parts are broken off by hand, rejecting all yellow or decayed leaves, and all the woody stems. The selected parts are carefully dried in the shade on bamboo racks, with frequent turning. When so far dried as to leave just sufficient moisture to favour slight fermentation, they are piled in heaps, and allowed to beat gently ; they are again spread out and dried (but not to absolute dry ness), and are immediately distilled. The distillation is effected by steam generated in a separate vessel, and at a pressure not exceeding 30 lb. a sq. in., the still being usually steam jacketed to prevent condensation. The yield of oil is about oz. from 1 lb. of leaves; it would be greater by high-pressure steam, but of ranker quality. This oil is sent to London in 22-oz. bottles. Quantities of the more or less inferior and mixed leaves are sent to France and Germany for distillation, but the oil from them is quite a different article. The sp. gr. of Indian and Singapore oils is 0.9554 and of a French sample, 1.0119, at 15*° (60° F.). It is much esteemed for perfumery purposes.