102 
Chloroform. 
Am.  Jour.  Pharm. 
Feb..  18U3. 
thoroughness  of  the  purification  to  which  the  crude  products  have 
been  subjected. 
If  the  character  of  the  finished  product  is  determined  by  the 
materials  used  we  should  find  the  products  from  chloral  hydrate 
and  spirits  of  wine  standing  alone  at  the  top  of  the  list  as  the  purest 
of  all  preparations.  Experience  shows  that  they  do  not  occupy 
this  position ;  products  from  other  and  less  pure  materials  being  in 
many  cases  found  to  excel  them  in  purity,  and  in  others  to  be  on  an 
equal  footing  with  them.  A  sample  of  chloral  hydrate  chloroform 
which  I  lately  examined  was  found  to  be  the  most  impure  of  a 
series  representing  all  the  different  brands,  and  the  crude  product 
from  chloral  hydrate  to  be  more  impure  and  more  difficult  to  purify 
than  similar  products  from  impure  raw  materials  ;  in  fact,  the  pro- 
duction of  chloroform  from  it  is,  I  believe,  being  abandoned, 
because  of  the  difficulty  experienced  in  its  purification. 
So  long  as  it  remains  impossible  to  determine  the  source  from 
which  pure  chloroform  has  been  obtained,  and  chloroform  prepared 
from  the  purest  materials  is  found  to  contain  more  impurity  than 
others  from  impure  sources,  the  advocates  of  the  pure  raw  material 
product  as  the  only  pure  one  cannot  reasonably  expect  confidence  to 
be  placed  in  their  statement,  when  pure  products  are  known  to  be 
obtained  from  either  source ;  and  their  position  is  still  further 
weakened  by  the  fact  that  they  are  unable  to  tell  one  pure  chloro- 
form from  another  without  consulting  the  label,  and  even  then  they 
may  be  wrong,  if  the  samples  have  not  been  correctly  marked. 
At  present  there  are  chloroforms  prepared  from  at  least  five  dif- 
ferent sources,  but  I  have  no  hesitation  in  saying  that  two  different 
brands — which  mayor  may  not  be  prepared  from  the  same  material — 
are  all  we  require  ;  one  of  the  highest  degree  of  purity  for  anaes- 
thetic purposes,  and  a  second,  not  so  highly  purified,  for  the  use  of 
manufacturers. 
If  what  has  been  said  regarding  the  effects  of  purification  is 
true — and  I  think  there  can  be  no  doubt  about  it — it  is  evident  that 
purification  is  the  only  factor  which  determines  the  quality  of  all 
chloroform,  and  that  it  has  been  and  is  successfully  used  to  level  up 
to  a  state  of  equal  purity  crude  products  of  all  kinds. 
The  purest  chloroform  therefore  must  be  that  which — irrespec- 
tive of  origin — contains  the  smallest  quantity  of  impurity. — Phar. 
Jour,  and  Trans.,  Decb.  24,  1892,  p.  505. 
