CHLOROFORM  NOT   DECOMPOSED  BY  SUNLIGHT. 
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place  for  two  weeks,  it  was  undergoing  complete  decomposition. 
The  decomposition  of  chloroform  of  high  specific  gravity,  ac- 
cording to  these  experiments,  appears  to  be  caused  by  the  oxy- 
gen of  the  atmosphere.  The  gaseous  products  of  decomposition 
in  these  cases  were  principally  hydrochloric  acid  and  chloro-car- 
bonic  oxide  (COC1.) 
Good  chloroform,  according  to  these  experiments,  is  not  de- 
composed in  contact  with  the  sunlight  and  air ;  therefore,  the 
direction :  "  In  vasis  denigratis,  bene  clausis  et  loco  obscuro 
caute  servetur,"  is  unnecessary  for  good  chloroform  of  the 
officinal  specific  gravity,  and  troublesome  to  the  apothecary.  It 
has  some  value  in  regard  to  chloroform  of  a  higher  specific 
gravity,  because  its  decomposition  occurs  sooner  under  the  influ- 
ence of  light ;  but  it  is  superfluous,  because  the  decomposition 
of  such  chloroform  is  not  prevented  by  the  exclusion  of  the  light. 
It  would  have  been  more  correct  to  insist  on  the  keeping,  by 
the  apothecaries,  of  chloroform  of  the  officinal  specific  gravity, 
and  thus  to  compel  the  druggists  to  sell  only  such  chloroform. 
It  appears  to  me  even  very  appropriate  to  adopt  officially  the 
reaction  of  the  sunlight  upon  chloroform,  for  it  is,  without  ques- 
tion, the  surest  test,  which  has  only  the  single  fault,  that  with 
us  (in  Berlin)  it  is  scarcely  practicable  during  the  winter  for  the 
want  of  sunny  warm  days. 
I  disapprove  entirely  of  the  use  of  blackened  bottles  as  shop 
bottles,  because  they  are  unsightly  and  require  great  care  in 
filling  and  pouring  out.  They  might  be  replaced  by  a  more  ap- 
propriate arrangement. 
Whence  and  from  whom  the  opinion  or  assertion  originated, 
that  chloroform  is  decomposed  by  the  sunlight,  I  could  not  ascer- 
tain. But  it  came  hardly  from  a  competent  source,  and  it  is 
therefore  to  be  regretted  that  it  has  received  unqualified  credit. 
—Pharm.  Central  Halle,  1867,  211—243. 
Remarks. — In  the  essay,  published  in  this  number  of  the 
Journal,  I  believe  to  have  shown  that  my  experiments  were  made 
with  pure  chloroform,  which  Dr.  Hager  has  not  proven.  Our 
summer  temperature  frequently  exceeds  35°  C.  in  the  shade, 
and  this  difference  in  the  temperature  may  account  to  a  certain 
21 
