OBSERVATIONS ON NICOTINE, ETC. 
69 
solution of a salt of lime or baryta, and an excess of carbo- 
nic acid passed into the solution, 1 equiv. of carbonate of 
lime or baryta is precipitated for every 2025 of nicotine. 
Nicotine must exist in the tobacco in the state of a salt ; 
for the aqueous, alcoholic and aethereal solutions of this 
plant behave precisely as if they contained a salt of nico- 
tine. Nicotine absorbs moisture from the atmosphere, but 
it may be completely deprived of water, aether, and ammo- 
nia by placing it over mercury in a bell glass full of hydro- 
gen, by the side of a capsule containing concentrated sulphu- 
ric acid. 
The amount of nicotine in leaf or manufactured tobacco 
may be accurately ascertained by a simple and easy pro- 
cess. 10 grms. of tobacco are exhausted with ammoniacal 
aether in a continuous distillatory apparatus, the ammonia- 
cal gas expelled from the nicotine solution by boiling, then 
decanted, and, after evaporation of the aether, neutralized 
with a solution of sulphuric acid of known strength. This 
process will be applicable, with some slight modifications, 
to most of the organic alkalies. Its accuracy was proved 
by ascertaining, — 1st, that the displacement of the nicotine 
by ammonia and the exhaustion by the aether are perfect; 
2d, that merely boiling the solution of nicotine suffices to 
expel the ammoniacal gas dissolved ; 3rd, that during this 
boiling no nicotine is lost; 4th, that a proportionality is 
found between different weights of nicotine, and the quan- 
tities of normal liquid required for their neutralization; 5th, 
that there is no other substance besides the nicotine capa- 
ble of absorbing the acid; 6th, that if the tobacco contained 
any other bases than nicotine, they would not interfere ; 
lastly, nearly the whole of the nicotine contained in 10 
grms. of Lot tobacco was extracted, purified, weighed and 
analysed; the weight was 0.766, and should have been, ac- 
cording to the test with the normal solution, 0.796. 
The following amounts of nicotine were indicated by 
