Am.  Jour.  Pharm.  ) 
July  1,  1873.  ) 
Carbolic  Acid  and  Creasote. 
291 
in  text- books,  although  carbolic  acid  is  and  probably  ever  will  be  its 
common  name. 
Carbolic  acid  is  produced  by  the  action  of  nitrous  acid  on  anilin, 
and  by  the  dry  distillation  of  gum  benzoin,  quinic  acid,  chromate  of 
pelosina,  salicylic  acid,  coal  and  the  resin  of  Xanthorrhoea  hastilis.  It 
is  found  in  the  urine  of  the  horse,  cow  and  man,  and  in  castor.  It  is 
ulso  reported  as  having  been  obtained  from  a  plant  growing  on  the 
high  lands  of  India  (the  Andromeda  Leschenaultii),  which  is  said  to 
yield*  a  very  pure  quality,  less  deliquescent  than  that  made  from  coal- 
tar  oil,  but  at  a  much  greater  cost.  It  forms  the  chief  constituent  of 
the  acid  portion  of  coal-tar  oil,  from  which  it  is  generally  obtained 
by  the  process  given  below. 
The  coal-tar  oil  is  subjected  to  distillation  in  a  retort  furnished 
with  a  thermometer,  and  the  portion  that  passes  over  between  the 
temperature  of  150°  and  200°  C.  (302°  and  390°  F.),  is  collected 
apart.  This  product  is  then  mixed  with  a  hot  strong  solution  of  caus- 
tic potash  and  left  to  stand,  whereby  a  whitish,  somewhat  crystalline 
pasty  mass  is  obtained,  which,  by  the  action  of  water,  is  resolved  into 
a  light  oily  liquid  and  a  dense  alkaline  solution.  The  latter  is  with- 
drawn by  a  siphon,  decomposed  by  hydrochloric  acid,  and  the  sepa- 
rated oil  purified  by  contact  with  calcium  chloride,  and  redistillation. 
It  is  then  exposed  to  a  low  temperature,  and  the  crystals  formed  are 
-drained  from  the  mother-liquor  and  carefully  preserved  from  the  air. 
Pure  carbolic  acid  forms  long  colorless  prismatic  crystals,  which 
melt -at  35°  C.  (95u  F.),  to  an  oily  liquid,  boiling  at  180°  G.  (356° 
and  greatly  resembling  creasote  in  many  particulars.  It  is  so- 
luble in  about  fourteen  parts  of  water,  freely  soluble  in  alcohol,  gly- 
cerin, ether,  and  strong  acetic  acid,  and  gives  no  acid  reaction  to  test 
paper.  It  is  very  deliquescent,  absorbing  moisture  from  the  atmo- 
sphere with  avidity  and  liquefying.  It  coagulates  albumen  readily, 
and  is  therefore  a  powerful  antiseptic.  Sulphur  and  iodine  dissolve 
in  it.  Nitric  acid,  bromine,  and  chlorine  attack  it  with  energy,  form- 
ing substitution  products,  all  of  which  are  of  an  acid  character.  It 
also  forms  substitution-products  with  sulphuric  acid,  and  is  dissolved 
by  alkalies,  forming  salts  called  phenates.  It  reduces  mercuric  oxide 
at  the  boiling  point ;  separates  silver  from  the  nitrate;  reduces  the 
peroxide  of  lead  to  the  protoxide  ;  and  upon  heating  it  with  arsenic 
acid  forms  a  yellow  substance  called  xanthophenic  acid.    One  of  the 
*  From  its  volatile  oil,  of  the  composition  of  oleum  gaultheriae.— Editor. 
