Am  octu"'i87h;.rm'}  Nitro-Benzole  in  Alcoholic  Beverages.  497 
is  converted  into  a  dark-brown  resinous  substance,  which  is  insoluble 
in  water  (Maisch).  Alcohol  and  ether  dissolve  it,  from  which  solutions 
it  can  be  obtained  in  yellow  crystals  on  evaporation  (Zinin's  azoxy- 
benzid).  Another  reaction,  advised  by  DragendorfF,  will  also  allow 
the  detection  of  nitro-benzole,  viz.  :  The  oily  residue  of  the  etherial 
extraction  is  dissolved  in  a  small  quantity  of  alcohol ;  on  adding  a  piece 
of  sodium  the  liquid  will  assume  a  dark-brown  color  and  pasty  con- 
sistence in  presence  of  nitro-benzole,  disengaging  at  the  same  time  a 
gaseous  substance,  the  formation  of  which  is  due  to  the  presence  of 
alcohol. 
As  to  the  conversion  of  nitro-benzole  into  anilin  and  the  production 
of  its  characteristic  color-reactions,  I  can  recommend  the  following 
modus  operandi  from  my  own  experience  : 
A  small  quantity  of  the  etherial  extract  of  the  residue  on  distillation, 
previously  alluded  to,  is  placed  in  a  test-tube  and  evaporated  to  dryness 
at  about  ioo°F.  A  few  drops  of  dilute  hydrochloric  acid  and  a  small 
quantity  of  very  fine  iron  filings  or  ferrum  hydrogenio-reductum, 
together  with  a  sufficient  quantity  of  water,  are  then  introduced  in  the 
same  test-tube.  Nitro-benzole,  if  present,  thus  will  be  converted  into 
anilin  by  the  action  of  hydrogen  in  statu  nascendi,  according  to 
the  following  equations:  3Fe+6HCl=3FeCl2+3H2 ;  C6H5N02-f 
3H2— C6H7N+2H20  ;  or  expressed  in  one  equation:  C6H5N02-f 
6HCl+3Fe=3FeCl2+C6H7N+2H20.  As  soon  as  the  oily  drops  of 
nitro-benzole  have  disappeared— no  matter  whether  the  iron  is  totally 
dissolved  or  not1 — the  supernatant  liquid  is  poured  off  into  another 
test-tube.  It  consists  of  ferrous  chloride,  FeCl2,  and  hydrochlorate  of 
anilin,  C6H8NC1,  or  [C6H5.NH2.HC1].  On  addition  of  caustic  soda 
solution  iron  precipitates  as  ferrous  oxyhydrate,  while  anilin  is  regener- 
ated and  can  be  extracted  and  separated  on  shaking  with  ether,  etc.,  in 
the  usual  manner.  The  etherial  extract  is  evaporated  on  a  watchglass, 
leaving  an  oily  residue  of  anilin,  which,  on  addition  of  a  few  drops  of 
hydrochloric  acid  and  a  small  crystal  of  potassic  chlorate,  KC103,  is 
converted  into  a  beautiful  blue  pigment.  The  color  changes  gradually 
into  a  light  green  and  disappears  entirely  in  a  short  time,  particularly  in 
presence  of  small  quantities  of  anilin,  as  in  this  case.    By  placing  the 
1  It  must  be  remembered  that  anilin  is  strong  enough  a  base  to  decompose  ferrous 
and  ferric  salts,  and  therefore  will  be  in  the  above  solution. 
32 
