Am.  Jour.  Pharm.l 
March,  1894.  j 
Crude  Carbolic  Acid. 
115 
lected,  the  receiver  is  changed,  and  the  next  62^  cc.  collected  apart. 
The  residue  in  the  retort  is  cresylic  and  higher  acids.  The  62^  cc. 
obtained  as  a  second  fraction  is  cooled,  and  the  solidifying  point 
ascertained  by  a  thermometer  placed  in  the  liquid.  These  crude 
carbolic  acids  are  sold  as  500,  6o°  or  yo°  acids,  meaning  thereby 
that  the  second  fraction  of  62^  cc.  crystallizes  at  500,  6o°  or  700 
F.  That  containing  the  most  crystal  acid  showing  the  highest 
melting  point. 
A  good  quality  of  6o°  English  crude  carbolic  acid  distilled  as 
follows : 
Per  Cent, 
To  180,   17    (n  p.  c.  water) 
"  185,  •  .  ■   21 
"  190,   71 
"  195,   88 
"  200,  -  .  .  93 
"  205,   95 
The  portion  representing  the  62^  cc.  distilling  between  1 84°-^ 
and  1930. 
A  very  good  grade  of  light  oil  must  be  used  to  obtain  such  an 
acid,  if  a  higher  fraction  of  the  tar  is  extracted,  the  acid  obtained 
shows  a  correspondingly  higher  boiling  point. 
The  following  acid  was  extracted  from  the  first  portions  of  the 
dead  oil : 
Per  Cent. 
To  180,   14    (11  p.  c.  water) 
"  190,   20 
"  195,   55 
"  200,   74 
"  205,   82 
"  210,   88 
"  220,   91 
"  230,  .  .  .  .   93 
The  62^2  cc.  of  this  acid  did  not  crystallize  until  cooled  to  25 0  F. 
If  insufficient  soda  is  used,  it  would  be  possible  to  extract,  even 
from  an  oil  of  this  nature,  a  certain  amount  of  acid  rich  in  phenol. 
Phenol  has  a  greater  affinity  for  soda  than  its  homologues,  therefore, 
if  one-half  the  soda  necessary  for  complete  extraction  is  used,  the 
solution  will  contain  a  greater  proportion  of  phenol  than  if  the 
material  was  extracted  completely. 
This  is  clearly  shown  by  the  following  experiment.    A  sample  of 
