io8 THE USES OF PLANTS. 



the narcotic poison Daturine, an isomer of Atropine, 

 valuable as a sedative, and therefore the leaves are 

 employed as cigars in asthma.* 



Hyoscyamus niger, L., HENBANE, a British plant, 

 cultivated on a small scale for medicinal purposes, is 

 sedative, anodyne, or hypnotic, and is used instead 

 of opium. It contains an alkaloid, Hyoscyamine, 

 C 15 H 23 NO 3 , which acts on the iris like Atropine.^ 



TOBACCO, the dried leaves of Nicotiana Tabacum, 

 L., and N. rustica^ L., natives of America, is but little 

 used medicinally, though its active principle, the vola- 

 tile oily alkaloid Nicotine, C 10 H 14 N 2 , is a powerful 

 narcotic poison. It is produced in the drying leaf by 

 a fermentative process, but is mainly destroyed when 

 the tobacco is burnt. The enormous growth of the 

 use of this substance in Great Britain, as in the rest of 

 the Old World, since its introduction in the sixteenth 

 century, may be gauged from the facts that over 

 .9,000,000 was paid on it as Customs duty in the 

 year 1886-7, tne tariff on unmanufactured tobacco 

 being 33. 6d. per lb., and that about 51,000,000 lb., 

 or if lb. per head of the population, was retained for 

 home consumption during the same year. By far the 

 greater part of this supply comes from the United 

 States. SNUFF is prepared from the stalks and veins 

 of the leaves. Tobacco has recently been experi- 

 mentally cultivated in this country, without much 

 success.J 



* De Candolle, ' Geographic Botanique,' ii (1855), p. 731. 



f Bentley and Trimen, iii., pi. 194. 



j Lock, C. G. W., ' Tobacco : Growing, Curing, and Manu- 

 facturing ; a Handbook for Planters in all Parts of the World/ 

 8vo., 1886. 



