222 
REMARKS  ON  CHLORINE  WATER. 
rine  will  not  only  be  obtained,  but  the  preparation  will  succeed 
more  quickly  than  by  the  Edinburgh  method,  although  the  con- 
scientious pharmacopolist  may  be  put  to  the  trifling  expense  of 
a  gas-bottle  and  two  suitable  glass  tubes  ;  the  apparatus  itself, 
with  a  little  care,  may  be  used  for  a  long  time. 
The  preparation  of  the  chlorine  water  by  the  other,  or  Edin- 
burgh method,  is  under  all  circumstances  objectionable,  notwith- 
standing the  language  of  the  Dispensatory,  page  894, — "contain- 
ing a  little  sulphate  of  soda,  which  does  not  interfere  with  its 
medicinal  properties  ;"  it  contains  this  solution  of  chlorine  with 
the  sulphate,  and  other  things  which  it  ought  not  to  contain  ;  and* 
in  its  internal  or  external  application,  effects  may  be  produced 
very  different  from  those  looked  for  by  the  physician,  who  thinks 
he  is  using  a  pure  article  instead  of  a  very  impure  one. 
The  chlorine  water  strictly  made  according  to  the  Edinburgh 
formula,  contains  no  lead,  and  according  to  repeated  experiments 
recently  made  by  me  on  various  samples  of  the  article  obtained 
from  a  drug  store,  contains  also  free  sulphuric  acid,  copper, 
etc.,  etc.  The  red  oxide  of  lead  always  contains  copper  in  vary- 
ing quantities,  and  which  may  be  se^en,  page  574  of  the  United 
States  Dispensatory,  under  the  article  "  Plumbi  Oxidum  Ru- 
brum;"  it  even  constitutes  a  material  portion  of  the  chlorine  water 
prepared  by  this  objectionable  method.  I  have  found  in  one 
ounce  of  this  solution  of  chlorine  : — 
9.0920  grains  of  NaO,  S03  -j-11.4637  HO=20.5557  grains  of  NaO,S03  -f  10HO, 
5.8429       «        S03  =to  7.688  S03  +HO  at  1.842  sp.  gr.  {  acid  of 
0.0200  of  a  grain  of  NaCl, 
0.342  to  0.443  of  a  gr.  of  CuO  S03=to  from  0.563  to  0.695  of  a  gr.  CuOSQ3+5HO, 
Traces  of  sulphate,  of  peroxide  of  iron,  of  chloride  of  iron,  of 
chloride  of  copper,  of  sulpnate  of  lime  and  of  sulphate  of  mag- 
nesia. The  two  last  derived  from  the  impurities  of  the  muriate 
of  soda,  that  is,  from  the  chloride  of  sodium  and  chloride  of 
magnesium,  contained  in  it. 
The  presence  of  copper  can  be  easily  detected  by  evaporating 
chlorine  water  a  little  in  a  dish  of  glass  or  porcelain,  and  then 
adding  a  solution  of  any  caustic  alkali  as  long  as  the  liquid  re- 
acts still  a  little  acid,  and  then  by  putting  into  it  a  polished 
iron  rod,  on  which  the  copper  will  be  precipitated  in  a  metallic 
state;  or  a  little  more  caustic  ammonia  may  be  added  to  the 
