TRANSACTIONS OF THE SECTIONS. 127 



Products of the Combustion of Tobacco. — Some recent researches on this subject 

 had led the author to the fact, that these products are much more complex than 

 had been supposed. He described an apparatus which was, in fact, an automaton 

 smoker, by which he had been enabled to have various kinds of tobacco and cigars 

 smoked by means of a bellows, the smoke which, in the case of a man, would 

 enter the mouth, being all caught and subjected to analysis. The results of these 

 inquiries had led him to the determination of the following bodies as products of the 

 combustion of tobacco : — (1) water ; (2) free carbon ; (3) ammonia ; (4) carbonic 

 acid ; (5) an alkaloidal principle, called nicotine ; (6) tm empyreumatic substance ; 

 (7) a resinous bitter extract. 



Physical Projierties of the Component Parts. — The water is in the form of vapoUr. 

 The carbon is in the form of minute particles, suspended in the water-vapour, and 

 giving to the eddies of smoke their blue colour. The ammonia is in the form of 

 gas combined with carbonic acid. The carbonic-acid gas is partly free and partly 

 in combination with ammonia. The nicotine is a non-volatUe body, an alkaloid 

 which remains in the pipe. The empyreumatic substance is a volatile body, ha'V'ing 

 an ammoniacal nature, but the exact composition of which is as yet unknown ; it 

 is this that gives to the smoke its peculiar odom- ; it adheres very poweifully to 

 woollen materials, and in the concentrated form is so obnoxious as almost to be 

 intolerable. The bitter extract is a resinous substance, of dark colour, and of in- 

 tensely bitter taste ; it is, probably, a compound body, having an alkaloid as its 

 base ; it is not volatile, and only leaves the pipe by being carried along the stem 

 in the fluid form. 



Variations in different kinds of Tobacco. — The greatest variations exist in various 

 kinds of tobacco. Simple tobacco that has not undergone fermentation yields very 

 little free carbon, much ammonia, much carbonic acid, little water, none or the 

 smallest possible trace of nicotine, a vevy small quantity of empyreumatic vapour, 

 and an equally small quantity of bitter extract. Latakia tobacco yields these same 

 products only. Bristol bird s-eje yields large quantities of ammonia and very 

 little nicotine. Turkish yields much ammonia. Shag tobacco yields all the pro- 

 ducts in abundance ; and the same maj' be said of pm-e Havanua cigars. Cavendish 

 varies considerably : some specimens, which are quickly dried, are nearly as simple 

 as Latakia ; other specimens, which are moist, yield all the products in great 

 abundance. Pigtail yields every product most abundantly. The little Swiss cigars 

 yield enoi-mous quantities of ammonia, and Manillas yield very little. 



Physiological Effects of the compounds named above. — The water-vapour is inno- 

 cuous. The carbon settles on the mucous membrane and irritates the throat. 

 The carbonic acid is a narcotic, if it be received into the lungs. The ammonia 

 causes dryness and biting of the mucous membrane of the throat, and increases 

 the flow of saliva ; absorbed into the blood, it renders the fluid too thin, causing 

 irregularity of the blood-corpuscles ; it also causes, when absorbed in large quan- 

 tities, suppression of the biliary secretion and yellowness of skin ; it quickens and 

 then reduces the action of the heart, and, in young smokers, it produces nausea. 

 The empyreumatic substance seems to be almost negative in its effects, but it gives 

 to the tobacco-smoke its peculiar taste, and it is this substance that makes the 

 breath of confirmed smokers so unpleasant. Nicotine is scai-cely ever imbibed by 

 the cleanly smoker ; it affects those only who smoke cigars by holding the cigar in 

 the mouth, and those who smoke dii'ty pipes saturated with oily matter : its effects 

 when absorbed are very injimous; it causes palpitation, tremor, and irregTdar 

 action of the heart, tremor and imsteadiness of the muscles generally, and great 

 prostration ; it does not, however, produce nausea or vomiting. The bitter extract 

 IS the cause of vomiting and nausea when it is absorbed ; both it and the nicotine 

 are always received into the mouth in solution, and produce their effects either by 

 direct absorption from the mouth or by being imperceptibly swallowed and taken 

 into the stomach. 



Mode of Smohiny. — The greatest difference arises &om the manner of smoking. 

 Those who use clean long pipes of clay feel only the eflects of the gaseous bodies 

 and the free carbon. Wooden pipes and pipes with glass stems are injurious. 

 Cigars, smoked to the end, are the most injmious of all. To be safe, a cigar ought 

 to be cast aside as soon as it is half smoked ; and every cigar ought to be smoked 



