478 LABIATvE. 



lavender, it is said that the oil which comes over in the earlier part of 

 the operation is of supei'ior flavour. 



We have no accurate data as to the produce of oil obtained in the 

 ordinary way, but it is universally stated to vary extremely with the 

 season. Warren^ gives it as 10 to 12 lb., and in an exceptional case as 

 much as 24 lb. from the acre of ground under cultivation. At Hitchin,^ 

 the yield would appear to approximate to the last-named quantity. 

 The experiments performed in Bell's laboratory as detailed above, show 

 that the flowers deprived of stalks afforded on an average exactly i;^ 

 per cent, of essential oil. 



Oil of Lavandula vera is distilled in Piedmont, and in the 

 mountainous parts of the South of France, as in the villages about 

 Mont Ventoux near Avignon, and in those some leagues west of 

 Montpellier (St. Guilhen-le-de'sert, Montarnaud and St. Jean de Fos) — 

 in all cases from the wild plant. This foreign oil is offered in com- 

 merce of several qualities, the highest of which commands scarcely 

 one-sixth the price of the oil produced at Mitcham.^ The cheaper sorts 

 at least are obtained by distilling the entire j^lant. 



Chemical Composition— The only constituent of lavender flowers 

 that has attracted the attention of chemists is the essential oil (Oleum 

 Lavandulae). It is a pale yellow, mobile liquid, varying in sp. gr. from 

 0"87 to 0"94 (Zeller), having a very agreeable odour of the flowers and a 

 strong aromatic taste. The oil distilled at Mitcham (1871) we find to 

 rotate the plane of polarization 4*2° to the left, in a column of 50 mm. 



Oil of lavender seems to be a mixture in variable proportions of 

 oxygenated oils and stearoptene, the latter being identical, according to 

 Dumas, with common camphor. In some samples it is said to exist to 

 the extent of one-half, and to be sometimes deposited from the oil in 

 cold weather; we have not however been able to ascertain this fact. 

 The oil according to Lallemand (1859) appears also to contain compound 

 ethers. 



Commerce — Dried lavender flowers are the object of some trade 

 in the south of Europe. According to the official Tableau general du 

 Commerce de la France, Lavender and Orange Flowers (which are not 

 separated) were exported in 1870 to the extent of 110,958 kilo. 

 (244,741 lb.), — chiefly to the Barbary States, Turkey and America. 

 There are no data to show the amount of oil of lavender imported into 

 England. 



Uses — Lavender flowers are not prescribed in modern English 

 medicine. The volatile oil has the stimulant properties common to 

 bodies of the same class and is much used as a perfume. 



Other Species of Lavender. 



1. Lavandula Spica DC. is a plant having a very close resemblance 

 to L. vera, of which Linnaeus considered it a variety, though its dis- 

 tinctness is now admitted. It occurs over much of the area of L. vera, 

 but does not extend so far north, nor is it found in such elevated situa- 



^ Pkarm. Journ. vi. {IS65) 257. Chester quarts" of oil. — One Winchester 



- Ibid. i. {I860) 278. The statement is quart = 282 litres, 

 that an acre of land yields " about G Win- ^ The Mitcham oil fetches 30s. to G0«. 



per lb., according to the season. 



