26o 
Solution  of  Chlorinated  Soda. 
A.m.  Jour.  Pharm. 
June.  1904. 
And  yet  the  retailer  is  supposed  to  take  a  chlorinated  lime; 
macerate  with  three  successive  portions  of  water,  with  no  especial 
care  to  either  obtaining  a  definite  quantity  of  filtrate  or  of  insuring 
complete  exhaustion  of  the  lime  ;  treat  the  filtrate  with  warm  sodium 
carbonate  solution;  warm  the  mixture,  if  gelatinous;  and,  finally, 
filter  ;  to  do  all  this  in  open  vessels  and  still  get  a  finished  filtrate 
containing  26  of  the  26-25  grammes  of  chlorine  supposedly  contained 
in  the  original  substance. 
Verily,  this  result  is  what  our  German  friends  would  call  "  fast 
quantitativ,"  and  is  on  a  par  with  the  ease  and  simplicity  (theoreti- 
cal) of  the  Pharmacopceial  method  of  making  spirit  of  ammonia  and 
with  the  airy  directions  given  for  making  the  official  iodized  sulphur. 
Perhaps  some  hair-splitting  chemist,  by  some  miracles  of  chem- 
ical manipulation,  may  secure  perfect  results  from  the  Pharma- 
copceial methods  of  making  the  three  substances  just  cited ;  but  it  is 
the  opinion  of  the  writers  that  these  methods  are  far  beyond  skill  of 
the  retail  pharmacist  for  whom  the  recipes  are  originally  intended. 
Let  us  give  figures  obtained  in  the  manufacture  and  assay  of 
several  lots  of  Labarraque's  Solution  by  the  process  of  1890,  and  let 
it  be  explained  that  we  will,  in  the  tabulated  statements,  make  use 
of  the  following  abbreviations  : 
Labarraque  =  Solution  of  chlorinated  soda, 
Lime  =  Chlorinated  lime. 
Hypochlorite  Sol.  =  Solution  of  chlorinated  lime,  the  intermediate  product  in 
the  method  of  the  U.S. P.,  1890,  for  making  Labarraque. 
Lime  residue  =  The  chlorinated  lime  supposedly  exhausted  with  water  by 
the  process  of  1S90. 
In  the  first  two  experiments,  having  previously  found  the  lime 
deficient  in  chlorine,  the  amount  of  that  chemical  employed  in  the 
process  was  increased  in  direct  proportion  to  its  chlorine  deficiency, 
with  a  view  to  start  with  same  amount  of  chlorine  demanded  for 
official  chlorinated  lime.  This  necessitated  addition  of  extra  sodium 
carbonate  to  insure  complete  precipitation. 
The  titration,  as  mentioned  above,  was  performed  by  the  method 
of  the  U.S.P.,  1890,  adding  potassium  iodide  and  hydrochloric  acid 
to  a  definite  quantity  of  the  solution  and  titrating  the  liberated 
iodine  against  decinormal  sodium  hyposulphite  V.  S. ;  starch  muci- 
lage being  used  as  the  indicator.  In  the  following  tables  this  volu- 
metric solution  is  abbreviated  to  Thio. 
10 
