30       DEPORTMENT  OF  ALKALOIDS  WITH  REAGENTS,  ETC. 
salts  of  coma  are  distilled  with  solution  of  soda,  the  distillate 
contains  conia.  On  neutralizing  this  with  oxalic  acid,  evapora- 
ting to  dryness,  and  treating  the  residue  with  spirit  of  wine,  the 
oxalate  of  conia  formed  is  dissolved,  whilst  any  oxalate  of  am- 
monia that  may  be  present  is  left  undissolved.  As  conia  is  only 
sparingly  soluble  in  water,  and  dissolves  with  still  greater  diffi- 
culty in  solutions  of  alkalies,  a  concentrated  solution  of  a  salt  of 
conia  tnrns  milky  upon  addition  of  solution  of  soda.  The  minute 
drops  which  separate  unite  gradually,  and  collect  on  the  sur- 
face. 
3.  If  an  aqueous  solution  of  a  salt  of  conia  is  shaken  with 
solution  of  soda  and  ether,  the  conia  is  dissolved  by  the  ether.  If 
the  latter  is  then  allowed  to  evaporate  on  a  watch-glass,  the  conia 
is  left  in  yellowish- colored  oily  drops. 
4.  Concentrated  nitric  acid  imparts  a  fine  blood-red  tint  to 
conia ;  sulphuric  acid,  a  purple-red  color,  which  subsequently 
turns  to  olive-green. 
5.  Terchloride  of  gold  produces  a  yellowish- white  precipitate, 
insoluble  in  hydrochloric  acid ;  chloride  of  mercury,  a  copious 
white  precipitate,  soluble  in  hydrochloric  acid.  Bichloride  of 
platinum  does  not  precipitate  aqueous  solutions  of  salts  of  conia, 
the  conia  compound  corresponding  to  ammonia-bichloride  of  plati- 
num being  insoluble  in  spirit  of  wine  and  ether,  but  soluble  in 
water. 
6.  To  solution  of  iodine  in  iodide  of  potassium  and  water,  and 
to  solution  of  tannic  acid,  conia  comports  itself  the  same  as  nico- 
tina. 
7.  Chlorine  water  produces  in  a  mixture  of  water  and  conia  a 
strong,  white  turbidity. 
8.  If  an  aqueous  solution  of  conia  is  mixed  with  a  solution  of 
albumen,  the  albumen  coagulates.  Aniline  is  the  only  other 
volatile  vegeto-alkali  which  shows  this  reaction. 
The  volatile  alkaloids  are  easily  recognized  when  pure ;  the 
great  object  of  the  analyst  must  accordingly  always  be  to  obtain 
them  in  that  state.  The  way  of  effecting  this  is  the  same  for 
nicotina  as  for  conia,  and  has  already  been  given  in  the  forego- 
ing paragraphs,  viz.,  to  distil  with  addition  of  solution  of  soda, 
neutralize  with  oxalic  acid,  evaporate,  dissolve  in  alcohol,  evapo- 
