370 Chemical Observations and Experitnents on Tobacco. 



hue ; decrepitates before the fire, and seems to enjoy neutral proper- 

 ties. 



12. Nicotia. 



There is not a more delusive term in modern chemistry, than Lig- 

 nin : an analyst niight be induced by this term, to abandon his re- 

 searches on vegetables, after alcohol, ether and water, at all tempe- 

 ratures, had acted on them ; for, after digestion in these substances, 

 plants are supposed to be exhausted of their principles ; yet nothing 

 can be more gratuitously asserted. Querela was obtained from oak 

 bark thus depurated by ether, spirit and water, and Tobacco leaves 

 similarly treated, and forming what chemists would call Lignin, af- 

 forded a new alkali more strictly approximating to querela in chemi- 

 cal habitudes than to any other known salifiable base. 



Still Nicotia exists in a small quantity in the infusion and decoction 

 of the leaves ; but it may be more readily developed by treating with 

 sulphuric acid the Tobacco, well edulcorated with ether, alcohol and 

 water, and evaporating nearly to dryness. 



The crystals of the sulphate being carefully washed, may be de- 

 composed by aqua ammoniae, which, combining with the acid, precip- 

 itates Nicotia. 



This substance does not appear to be susceptible of a crystalline 

 form ; it is of a dull yellowish white color, tasteless, inodorous, plas- 

 tic, and pulverulent ; insoluble in ether, alcohol and water ; soluble 

 in excess of acids, and decomposed by heat ; all its salts are tasteless, 

 and insoluble, unless acid predominate, and may be readily decom- 

 posed by ammonia. Sulphate of nicotia crystallizes in asteroid 

 needles, which, under the microscope, assume the form of quadran- 

 gular prisms. It is soluble in water, and contains a slight excess of 

 acid, a circumstance which may serve to distinguish it from querela. 



Hydro-chlorate (muriate) of Nicotia is aggregated in stars, usually 

 formed of from five to six crystals. 



Borate of Nicotia is white, insoluble, and uncrystallizable. 



The most diagnostic property of Nicotia, is perhaps its entering 

 into solution with the vegetable acids, without forming with them any 

 crystalline compound. 



Philadelphia, Aug. 24th, 1829, No. S Lombard street. 



