ON  THE  PREPARATION  OF  CHLOROFORM.  421 
with  the  corresponding  compounds  of  quinia,  Von  Heyningen's 
^Squinia,  cinchonia  and  Erdman's  huanokia. — (^Arch.  d.  Pharm. 
cliii.  273-291.)  j.  m.  m. 
ON  THE  PREPARATION  OF  CHLOROFORM. 
By  Michael  Pettenkofer. 
Frequently  preparing  chloroform,  the  author  noticed  the  great 
difference  in  the  yield  when  operating  with  the  same  quantities 
of  chloride  of  lime  and  alcohol,  and  apparently  by  the  same 
process.  Changing  the  process,  using  a  chloride  of  lime  of 
which  the  active  chlorine  had  been  estimated,  and  dividing  the 
chloride  of  lime  carefully  in  the  liquid,  did  not  produce  an  even 
result ;  it  was  observed,  however,  that  the  yield  was  less  in  pro- 
portion to  the  time  which  the  mixture  had  been  allowed  to  stand 
previous  to  distillation. 
If  a  clear  solution  of  chloride  of  lime  is  mixed  with  alcohol, 
the  solution  turns  but  slightly  turbid  in  a  temperature  of  8 — 10° 
R.  ^50 — bb'^  F.,)  and  assumes  but  a  faint  odor  of  chloroform. 
The  turbidness  is  stronger,  and  increases  in  a  shorter  time  if 
exposed  to  a  temperature  of  88  to  100°  F.  Heated  to  150 — 
167°  F.,  the  mixture,  unless  too  dilute,  becomes  gelatinous  and 
evolves  gas-bubbles  of  evaporating  chloroform.  If  now  the 
mass  is  heated  to  167  or  185^  F.,  until  destitute  of  the  odor  of 
chloroform,  the  gelatinous  appearance  is  gone,  and  the  liquid 
contains  a  white  precipitate  of  carbonate  of  lime.  Besides  the 
odor  of  chloroform,  that  of  chlorine  becomes  apparent  in  pro- 
portion to  the  rapidity  with  which  the  mixture  is  heated  to 
boiling,  and  the  quantity  of  the  precipitate  is  proportionately 
diminished.  The  temperature  most  favorable  for  the  formation 
of  chloroform  lies  between  46  and  60°  R.,  (185  and  167°  F.) 
Below  112°  F.  the  yield  of  chloroform  is  always  decreased,  and 
the  more  so  the  longer  the  mixture  had  remained  at  a  lower 
temperature.  If  the  mass  is  quickly  heated  to  the  temperature 
of  boiling  water,  hypochlorous  acid  appears  to  be  evolved,  thus 
causing  a  loss  of  a  compound  requisite  for  the  formation  of 
chloroform. 
