Syrian Tobacco leaf (a) .612% American Chewing Leaf .935% Syrian Tobacco Leaf (b) 1.093% Chinese Tobacco Leaf 1.902% Turkish Coarse Cut 2.500% Golden Virginia (whole strips) 2.501% Gold Flake Virginia 2.501% Navy Cut (light) 2.530% Light Kentuckian 2.733% Navy Cut (dark) 3.64 % Best "Bird's Eye" 3.931% Cut Cavendish (a) 4.212% Best Shag (a) 4.907% Cut Cavandish (b) 4.970% Best Shag (b) 5.00 % Algerian Tobacco (a) 8.813% French Grown Tobacco 8.711% Algerian Tobacco (b) 8.90 % The average of a number of samples of Syrian tobacco showed 1 to 2% nicotine, Manila and Havana 1 to 3%, Virginia and Kentucky from 2 to 7%, and French tobaccos about 9%. Most of the nicotine in tobacco becomes volatilized and decomposed during combustion; a small part, however, may form a solution with the water which is also one of the combustion products. One of the decomposition products of nicotine is _Pyridine_ Pyridine is usually found in tobacco smoke. When condensed it is a colorless non-oily liquid and is considerably less toxic than nicotine. Reference will be made later on to the effects of nicotine and pyridine on the human system. _Potash_ Potash is important as on its amount depends the burning qualities of the tobacco. It is sometimes present in the ash to the extent of 30%, being converted into potassium carbonate by burning. Not only for free burning is the potash valuable, but also for the better volatilization of the nicotine and other substances. The more perfect the combustion, the fewer deleterious compounds are formed. Chlorides, if present, retard the burning of the tobacco, and hence a tobacco which contains a high percentage of chloride, even if it is rich in potash salts, is a poor burning tobacco and therefore faulty. While it is important that the burning should be free and the volatilization as perfect as possible, yet the smoker does not want his tobacco to burn too rapidly. To meet this some manufacturers prepare "slow burning" tobaccos generally by the addition of some chemical which checks the potash. The aroma and flavor of the tobacco depend to a great extent on the waxes, resins and oils, as well as on certain of the organic acids. REFERENCES U. S. DISPENSATORY. 1907 (19th Edition). KISSLING. _The Chemistry of Tobacco._ _Scientific American_ (Supp.) 1905, Vol. 60, No. 1560. CHUARD & MELLETT. _Variation de Nicotine dans les differents organes de la plante de Tabac._ Comp. Rend. Acad. d. Sc. (Paris) 1912. Vol. 155, p. 293. PEZZOLATO, A. _Conferenza Sulla Chimica applicato alla technologia del Tabacco._ (Rome. 1903.) WOLF, JACOB. _Der Tabak und die Tabak fabrikate._ Chapter III. Leipzig, 1912.