254 TOBACCO. 



smoked than well - burning cigars containing much 

 nicotine. 



The amount of nicotine in tobacco varies very much, 

 according to the sort of plant, the climate, the nature of 

 the soil in which the plant grew, the treatment received 

 during its growth, and the course adopted to prej)are the 

 leaf for the market. Dr. Nessler found that good Syrian 

 tobacco contained no nicotine, Havana tobaccos between 

 0*6 and 2'0 per cent., and German tobaccos between 0*7 

 and 3" 3 per cent. Schlosing found in French tobacco 

 nearly 8 • per cent, of nicotine. Fine tobaccos contain 

 generally little or no nicotine. Broughton found that 

 the amount of nicotine in Indian tobaccos varies very 

 much. The conditions favourable to the development of 

 nicotine in the plants are : — Soil in a bad physical state, 

 strong nitrogenous manure, a dry atmosphere, and pro- 

 bably a low temperature during the growth. 



According to Nessler, green and newly-cut tobacco- 

 plants contain no ammonia ; it is developed during the 

 drying and fermentation of the leaves, especially when 

 they assume a brown colour. Tobacco-leaves, which have 

 undergone a strong fermentation, contain more ammonia 

 than those slightly fermented. Fine tobaccos contain 

 generally less ammonia than coarser ones. In various 

 smoking-tobaccos, Nessler found : — Havana, • 2 per cent, 

 of ammonia ; Cuba, • 3 ; Syrian, 0*6; German, • 9 per 

 cent. Schlosing found Havana tobacco to contain 0*8 

 per cent. 



Nitric acid, consisting of nitrogen and oxygen, is 

 formed in animal and plant substances when decomposed 

 under the influence of atmospheric air and a sufficiently 



