182 APPENDIX. 
from pipes, while collidine was the prominent base in cigar-smoke. 
Vohl and Eulenberg conelude that the nicotine of tobacco is com- 
pletely decomposed during the process of smoking, and that the intense 
action of tobacco-smoke on the nervous system is due to the presence 
of bases of the pyridine series. There is no doubt that some 
observers have mistaken these bases for nicotine ; but Melsen’s: 
experiments (Dingl. Polyt. Jour., xlvii., 212) appear to be conclusive 
as to the presence of nicotine, which that chemist isolated in a 
condition fit for analysis, and to the amount of about 33 grammes for 
4; kilogrammes of tobacco smoked, or about one-seventh of the 
quantity originally present. (Adllen’s Com. Organ. Anal., iii., pt. 2.) 
A. Gautier has since observed that the volatile liquid products 
formed when tobacco is smoked in a pipe consist ehiefly of basic 
compounds. They contain a large proportion of nicotine, a higher 
homologue of nicotine C'\H'°N?, which pre-exists in tobacco leaves, 
and a base C°H°NO, which seems to be a hydrate of picoline, Other 
less volatile bases, including hydropyridines, are also formed. ‘These 
alkaloids result from the decomposition, at a comparatively low 
temperature, of the carbopyridic and carbohydropyridic or analogous. 
acids present in tobacco. (J. Chem. Soc., April, 1893.) 
Tho alkaloidal contents of the Seeds and 
Tincture of Datura Stramonium. 
The principal constituents of stramonium seeds, according to Fliic- 
kiger and Hanbury’s Pharmacographia (p. 461), are an alkaloid, 
existing in combination with malic acid, and a fixed oil, of which the 
seeds are said tocontain 25 per cent. The alkaloidal constituent 
was first isolated by Geiger and Hesse in 1833, and in 1850 was 
submitted to examination by Von Planta, who came to the conclusion 
that it was identical with atropine. This statement was subsequent- 
ly confirmed by E, Schmidt (Ber, der Deutsch. Chem. Ges., xiii., 
370), who, however, afterwards modified his views, and concluded 
that daturine was really a mixture, in varying proportions, of atropine 
and hyoscyamine (Archiv, der Pharmacie, xxii,, 3 9). 
‘ Ladenburg also showed (Berichte Chem. Ges., xiii., 909) that 
stramonium contains two alkaloids, which he designated heavy and 
light daturine, the former consisting of atropine and hyoscyamine, 
and the latter of hyoseyamine only. 
