ON  TOBACCO. 
211 
tinum  in  the  double  salts  of  the  volatile  bases,  of  the  following 
table  founded  on  previous  and  new  observations  of  Nessler, 
Winckler,  Procter,  myself  and  others. 
Principal  Reactions  of  the  Medicinal  Volatile  Bases, 
(w.  =  watery  solution,  s.  =  salts,  or  acid  solutions.) 
REAGENTS  ADDED  TO      AMMONIA.     TRIMETIIYLINA.  ANILINA 
NICOTINA. 
u  I 
LOBELINA. 
Iodine  in  Iodide 
of  Potassium- 
Tannic  Acid- 
Chloride  of  Mer-  ( 
cury  \ 
lodohydrargy- 
rate  of  Potas- 
sium  
Acetate  of  Lead.* 
Nitrate  of  Silver 
w.  Decolor 
ised. 
s.  No  change. 
w.  No  Pre- 
cipitate. 
s.  Precipi- 
tate ot  tan- 
nin if  con- 
centrated. 
w.  White 
precipitate. 
s.  No  preci- 
pitate; with 
caustic  KO 
orange  to 
brown  pre- 
cipitate. 
w.  White  to 
yellow  pre- 
cipitate, so- 
luble in  ex- 
w.  &  s.  Orange 
colored  precipi 
tate. 
Neutral  and 
alkaline  solu- 
tions ;  white, 
curdy  precipi- 
tate. 
w.  White  pr& 
cipitate. 
.  A  loose  mass 
'  pale  yellow 
crystals,  very 
soluble  in  ex- 
i  of  iodide 
of  potassium. 
&  caustic  KO; 
decomposed  by 
king  with 
water. 
w.  Precipitate 
which  re-dis 
solves  in  ex- 
Chloride  of  Gold  • 
Chloride  of  Pluti- 
numf  
Density  and  So- 
lubility  " 
w.  Brown- 
ish-black. 
10.  Reddish- 
yellow  pre- 
cipitate. 
i.  Grayish 
soluble  in  ni- 
tric acid. 
w.  Grayish- 
yellow,  insolu- 
ble in  hydro- 
chloric acid. 
Brown  solu 
tion,  after 
wards  a  pre 
cipitate,  or 
none. 
No  precipi 
tate. 
No  precipi 
tate. 
w.  Solution 
white  pre 
•ipitate,  solu- 
ble in  excess 
md  in  KI,re 
produced  by 
KO,  but  re- 
lissolved  by 
excess  of  the 
same. 
No  precipi 
tate. 
w,  No  pre- 
ipitate. 
w.  and 
brownish  red 
precipitate 
Whiti  s  h 
precipitate, 
soluble  in 
acids. 
vj.  White 
precipitate. 
w.  and  s. 
Yellowish 
precipitate, 
somewhat  so- 
luble in  ex- 
cess of  re- 
agent, and 
readily  so- 
luble in 
caustic  KO. 
w.  &  s.  Pale 
b  r  o  w  n  i  sh 
red  precipi 
tate. 
White  pre- 
cipitate, so- 
luble in  tan- 
nic and  other 
acids. 
w.  White 
precipitate. 
w.  &  s.  Same 
as  nicotina, 
Very  solu- 
ble ;  mixes 
with  water. 
Very  soluble 
mixes. 
Scarcely  so- 
luble ;  floats 
w.  At  first 
no  precipi- 
tate, but  a 
brownish- 
black  one  on 
heating. 
w.  Yellow- 
ish, curdy, 
insoluble  in 
HC1. 
Little  solu- 
ble: sinks. 
White 
precipitate, 
turning 
brownish, 
soluble  in 
ammonia,  at 
first  also  in 
nitric  acid. 
w.  Whitish, 
nsoluble  in 
UC1. 
Little  solu- 
ble: floats. 
w.  and 
Brownish- 
red  pre- 
cipitate. 
White 
precipi- 
tate,  solu- 
ble in  tan- 
nin and 
ammonia. 
io.  No  pre- 
cipitate. 
w.  and 
Pale  yel- 
low pre- 
ipitate, 
little  bo- 
luble  in 
excess  of 
reagent  or 
of  caustic 
KO. 
w.  White 
p  r  e ci pi- 
tate,  solu- 
ble in  am- 
monia and 
nitric  acid. 
w.  Pale 
yellow,  in- 
soluble in 
HC1. 
Little  so- 
1  u  b  1  e  ; 
floats. 
Course  of  Proceeding. — The  volatile  alkaline  substance  having 
been  obtained  in  form  of  a  concentrated  solution  in  water,  and 
*  In  the  watery  solution,  except  of  anilinn,  a  white  precipitate. 
t  Distinct  precipitate  only  from  nicotina,  which  dissolves  on  heating. 
