PREPARATION  OF  ARTIFICIAL  COLORING  MATTERS,  ETC.  251 
and  distilled  to  recover  the  solvent.  The  residue*of  the  distil- 
lation is  anileine,  or  aniline  violet. 
Mr.  Perkin  gives  the  following  directions  for  dyeing  with 
anileine  : — To  dye  a  lilac  or  a  purple,  an  alcoholic  solution  of 
the  coloring  matter  is  added  to  a  boiling  dilute  solution  of  oxalic 
and  tartaric  acids,  and  when  the  mixture  has  cooled,  the  mate- 
rials to  be  dyed  (silk,  cotton,  &c.,)  are  to  be  completely  im- 
mersed in  the  bath.  Mr.  Perkin's  patent  is  dated  August  26, 
1856.  In  the  early  part  of  1859,  M.  Yerguin,  a  chemist  at 
Lyons,  while  experimenting  with  aniline,  discovered  a  process 
for  converting  it  into  a  magnificent  purple-red  coloring  matter. 
M.  Verguiu  sold  his  process  to  MM.  Renard  and  Franc,  who 
patented  the  process  in  France,  on  the  8th  of  April,  1859,  and 
gave  the  new  coloring  matter  the  name  of  Fuchsine.  The 
process  is  as  follows : — A  mixture  of  ten  parts  of  aniline  with 
six  or  seven  of  anhydrous  chloride  of  tin  is  boiled  for  fifteen  or 
twenty  minutes.  The  mixture  at  first  turns  yellow,  then  becomes 
reddish,  and  ends  by  assuming  a  beautiful  red  color  when  seen 
in  thin  layers  ;  in  the  mass  it  appears  black.  Water  is  now 
added,  and  the  whole  is  heated  to  ebullition.  It  is  then  re- 
moved from  the  fire,  allowed  to  rest  a  moment  for  some  insoluble 
matters  to  deposit,  and  then  filtered  while  still  hot ;  the  residue 
is  exhausted  by  another  boiling  with  water.  The  filtered  liquor 
contains  the  coloring  matter  in  solution.  To  separate  it,  advantage 
is  taken  of  its  being  insoluble  in  a  saline  solution  ;  accordingly, 
chloride  of  sodium  or  a  neutral  tartrate  of  potash  or  soda,  in  a 
solid  state,  is  added  to  the  liquor,  and  as  the  salt  dissolves,  the 
coloring  matter  is  deposited.  It  may  then  be  separated  by  de- 
cantation  or  filtration. 
Fuchsine  may  be  employed  for  dyeing  either  in  aqueous 
solution,  without  a  mordant,  or  with  the  ordinary  saline  or  acid 
mordants,  always  excepting  the  mineral  acids,  which  alter  the 
color. 
A  red  color  is  also  obtained  by  acting  on  aniline  with  other 
anhydrous  metallic  chlorides,  bichloride  of  mercury,  perchloride 
of  iron,  protochloride  of  copper,  for  example.  In  October,  1859, 
MM.  Renard  and  Franc  added  to  the  above  three  anhydrous 
chlorides,  the  hydrate  of  bichloride  of  tin,  as  being  equally  able 
to  change  aniline  into  fuchsine.    A  second  addition  to  their 
