When tobacco is burned, chemical changes 
occur; the organic and other compounds are 
decomposed. The volatile matters pass off in 
the smoke if the combustion is complete, and 
the mineral ash remains. In ordinary pipe or 
other tobacco smoking, however, the combustion 
is not complete and many decomposition pro- 
ducts remain with the mineral ash. 
In tobacco smoke the following can usually 
be found: Furfurol, Marsh Gas, Hydrogen 
Sulphide, Hydrogen Cyanide, Organic Acids, 
Phenols, Empyreumatic Oils, Pyridine, Picoline 
Series and possibly some Nicotine. 
The ash left after complete combustion is 
important, as much of the smoking qualities of 
the tobacco depends on its constituents. An 
average sample gives the following analysis (in 
100 parts) : 
AVERAGE MINERAL CONTENTS OF TOBACCO ASH 
Potash: ieedaceyean dees ove een About 27% 
SOdA> Sos ete eee eeaee ees About 8% 
Dame ecko cio en ae haks About 40% 
MaBnGRh) coeuiis se tuewwaa seks About 9% 
Sodium Chloride ............... About 9% 
Sulphuric Acid ..............4. About 38% 
Silica ..... Bel ta he Lelia Anion Bes sim About 5% 
Lime Phosphate ............... About 4% 
