Rosmarini Oleum-Oil, of Rosemary.-The oil distilled from the flowering tops of Rosmarinus officinalis.

Characters.-Colourless, with the odour of rosemary, and a warm aromatic taste.

Composition.-Oil of rosemary has the usual composition of its allies, consisting of a terpene, isomeric with turpentine, Cl0Hl6, and a body allied to camphor.

Dose.-1 to 5 min,

Preparations. Spiritus Rosmarini.-1 in 50. Dose, 10 to 30 min.

Oil of Rosemary is also contained in Linimentum Saponis and Tinctura Lavandulae Composita.

Action And Uses

Rosemary resembles the other aromatic volatile oils in its action and applications. It is a favourite component of stimulating lotions.

Lavandulae Oleum-Oil of Lavender.-The oil distilled in Britain from the flowers of Lavandula vera.

Characters.-Colourless or pale yellow, with the odour of lavender, and a hot bitter aromatic taste.

Composition.-Oil of lavender is a mixture of a terpene, C10Hl6, and a substance allied to camphor.

Impurities.-Oils of spike and turpentine.

Dose.-1 to 5 min.

Preparations.

1. Spiritus Lavandulae

Spiritus Lavandulae. 1 in 50. Dose, 1/2 to 1 fl.dr.

2. Tinctura Lavandulae Composita

Tinctura Lavandulae Composita. Dose, 1/2 to 2 fl.dr.

Tinctura Lavandula Composita is contained in Liquor Arsenicalis.

Oleum Lavanduloe is an ingredient of Linimentum Camphorae Compositum.

Action And Uses

Lavender possesses the action of aromatic volatile oils in general, and is used in the same way. The tincture is a favourite colouring material for mixtures and lotions.

Menthae Piperitae Oleum-Oil of Peppermint.-The oil distilled in Britain from fresh flowering Peppermint, Mentha piperita.

Characters.-Colourless or pale yellow, with the odour of peppermint; taste warm and aromatic, succeeded by a sense of coldness in the mouth.

Dose.-1 to 5 min. menthae Viridis Oleum-Oil of Spearmint. -The oil distilled in Britain from fresh flowering Spearmint, Mentha viridis.

Characters.-Colourless or pale yellow, with the odour and taste of spearmint.

Lose.-1 to 4 min.

Composition.-Peppermint oil consists of a liquid terpene, and a stearoptene, peppermint-camphor or menthol, C10H10O, in colourless prisms, with the taste and odour of peppermint. Oil of spearmint has probably a similar composition.

Preparations. a. Of Peppermint:

1. Aqua Menthae Piperitae

Aqua Menthae Piperitae. 1 in 853, by distillation. Dose,

1 to 2 fl.oz.

2. Essentia Menthae Piperitae

Essentia Menthae Piperitae. 1 in 5. Lose, 10 to 20 min.

3. Spiritus Menthae Piperitae

Spiritus Menthae Piperitae. 1 in 50. Lose, 30 to 60 min.

Oil of Peppermint is also contained in Pilula Rhei Composita.

b. Of Spearmint:

Aqua Mentha Viridis.-1 in 853, by distillation. Lose. 1 to 2 fl.oz.

Action And Uses

Peppermint has the action of other aromatic volatile oils (see Caryophyllum, page 242), and is used accordingly. It is a favourite flavouring agent, with powerful carminative effects.

Menthol, the stearoptene of Mentha arvensis, and " Chinese oil of peppermint," have lately been used locally to relieve the pain of rheumatism, neuralgia, and toothache, as possessing in a marked degree the local anaesthetic, vascular stimulant, and disinfectant action of these oils, described under Terebinthinoe Oleum. It is of no real value as an antiseptic dressing.

Oleum Thymi-Oil of Thyme. (Not Officinal.) -A volatile oil distilled from Thymus vulgaris.