298 
ON  SULPHATE  OF  ANILIN. 
rious  breathing,  loss  of  strength,  dilated  pupils,  and  inflamma- 
tion of  the  mucous  membrane  of  the  mouth.  Dropped  into  the 
eye  it  does  not  dilate  the  pupil.  (Hoffman  in  Gmelin's  Hand- 
book, vol.  xi.  p.  249.) 
Preparation  of  Sulphate  of  Anilin. — Having  obtained  anilin 
by  the  foregoing  or  any  other  process,  the  sulphate  is  easily 
prepared  by  several  processes. 
Take  of  Anilin,  as  pure  as  possible,  500  grains. 
Sulphuric  acid,  250  " 
Distilled  water,  4  fluid  ounces. 
Mix  the  acid  with  the  water,  add  the  anilin  and  agitate  them 
together  until  a  thick  magma  is  formed  and  the  odor  of  anilin 
has  nearly  disappeared.  This  is  now  washed  with  strong  alco- 
hol until  free  acid  and  coloring  matter  is  removed;  then,  having 
pressed  the  drained  salt  between  the  folds  of  white  filtering 
paper,  it  is  dried  in  the  dark.  If  wanted  in  crystals,  the  white 
pulverulent  sulphate  thus  obtained  is  dissolved  in  boiling  alco- 
hol, which  is  allowed  to  cool  slowly  in  a  covered  vessel  in  a  dark 
place;  the  crystals,  when  formed,  should  be  drained  on  filtering 
paper  and  dried  in  the  dark. 
The  sulphate  may  also  be  made  by  dissolving  the  anilin  in 
two  fluid  ounces  of  alcohol,  95  per  cent.,  then  having  mixed  the 
sulphuric  acid  slowly  with  two  fluid  ounces  of  the  same  liquid, 
when  cool  add  it  to  the  solution  of  anilin.  The  sulphate 
thus  formed  is  washed  with  cold,  strong  alcohol,  pressed  in  bibu- 
lous paper,  and  dried  in  the  dark. 
Sulphate  of  anilin  is  an  odorless,  colorless  crystalline  salt 
when  entirely  pure,  but  when  exposed  to  air  and  light,  espe- 
cially if  moi3t,  it  changes  color  from  the  formation  of  fuscine, 
the  odor  of  anilin  being  also  apparent.  The  crystals  may  be 
dried  at  212°  without  decomposition  except  a  slight  change  of 
color,  but  at  a  higher  temperature  they  lose  first  water  and 
then  anilin,  and  an  acid  salt  remains,  which  on  being  yet  further 
heated  is  decomposed,  producing  sulphite  of  anilin,  ammonia 
and  odorin,  with  a  residue  of  carbonaceous  matter.  When  a 
grain  of  the  sulphate  is  put  in  14  grains  of  water  in  a  test  tube, 
and  repeatedly  shaken  for  an  hour,  a  slight  residue  remains  un- 
dissolved, indicating  that  water  at  60°  dissolves  about  6  per 
cent.    Absolute  alcohol,  cold,  dissolves  it  but  slightly,  but  at 
