Am.  Jour.  Pharni. 
July,  1893. 
Decomposition  of  Chloroform. 
355 
as  well  as  the  discordant  opinions  entertained  respecting  various 
obse  rved  features  of  the  decomposition. 
In  the  first  place  we  desire  to  express  our  satisfaction  at  finding  that 
in  regard  to  certain  leading  facts  there  is  complete  agreement  between 
Mr.  Brown  and  ourselves,  that  in  reality  he  has  furnished  further 
confirmation  of  the  accuracy  of  our  observations  as  recorded  in  the 
Archiv  der  Pharm.  for  1867  and  1868  (see  also  Amer.  Jour. 
Pilar.,  1867,  p.  72,  and  1868,  p.  289),  and  also  of  the  general  con- 
clusion deduced  from  our  investigations,  that  while  chloroform  is 
not  decomposed  by  the  action  of  sunlight  in  the  absence  of  oxygen, 
it  is  so  decomposed  when  oxygen  is  present,  yielding  as  products, 
chlorine,  carbon  oxychloride  (phosgene)  and  water.  In  regard  to 
the  ultimately  recognizable  results  of  this  decomposition  in  particu- 
lar instances  there  is,  however,  one  circumstance  which  exercises  an 
essential  determining  influence ;  but  it  is  not  always  sufficiently 
considered,  and  this  fact  has  given  rise  to  differences  of  opinion  as 
to  the  nature  of  the  decomposition  and  of  its  products.  Thus 
Professor  Ramsay  has  put  forth  the  opinion  that  the  only  products 
are  carbon  oxychloride  and  hydrochloric  acid,  whilst  others  main- 
tain that  in  addition  to  the  formation  of  those  products  there  is  also 
an  elimination  of  chlorine  in  the  free  state. 
We  have  no  doubt  that  this  difference  of  opinion  is  entirely  due 
to  want  of  attention  to  the  presence  of  alcohol  in  the  chloroform 
experimented  with,  and  to  misinterpretation  of  the  chemical  changes 
taking  place.    Whilst  recognizing  as  correct  the  first  two  equations  : 
4CHCI3  +  302  =4C0C12  +2H20  +  2C12 
and 
2C0C12  -f  2H20  =  2C02  -f  4HCI, 
given  by  Mr.  Brown  to  represent  the  decomposition,  we  think  it 
necessary  to  add  that  those  equations  apply  exclusively  to  the 
decomposition  of  chloroform  that  is  perfectly  free  from  alcohol. 
Many  years  ago  we  succeeded  in  proving  that  the  well-known 
influence  of  alcohol  in  preserving  chloroform  from  decomposition  is 
due  to  the  alcohol  taking  up  and  chemically  combining  with  the 
deleterious  products  resulting  from  the  decomposition,  so  as  to 
render  them  innocuous.  More  recently  this  fact  has  also  been 
pointed  out  in  the  paper  published  by  us  on  the  preservation  of 
