CHLORINATED  LUNAR  CAUSTIC. 
239 
possible  ;  and  as  there  is  a  very  simple  test  by  which  the  puri- 
ty of  lunar  caustic  may  be  established,  physicians  can  protect 
themselves  against  this  adulteration.  The  test  will  be  found  at 
the  end  of  this  note. 
To  make  the  chlorinated  lunar  caustic,  I  originally  added  a 
small  quantity  of  chloride  of  sodium  to  the  nitrate  of  silver,  so 
that  when  the  mass  was  fused,  about  eight  per  cent,  of  chloride 
of  silver  resulted  from  the  decomposition.  This  method  was 
found  objectionable,  as  it  introduced  a  small  quantity  of  nitrate 
of  soda  in  the  mass,  so  the  following  is  the  method  proposed  for 
general  adoption : 
Take  Cryst.  Nitrate  Silver,      .  .        .480  grs. 
Dry  Chloride  Silver,  .        .        .        .        38$  « 
Fuse  the  mixture,  and  cast  in  the  ordinary  moulds. 
Dr.  Squibb  suggests  the  following  method : 
Take  Nitrate  Silver,  .....    960  grs. 
Muriatic  Acid,      ....  40  " 
Distilled  Water,  •        .        J  fluid  oz. 
Mix  the  acid  and  water  in  a  suitable  vessel,  add  the  nitrate  of 
silver,  reduce  to  dryness,  fuse,  and  cast  in  moulds  ;  this  intro- 
duces five  per  cent,  of  chloride  of  silver  in  the  lunar  caustic. 
Either  of  these  methods  may  be  employed,  but  I  prefer,  for 
manufactural  purposes,  the  first  formula,  as  the  dry  materials 
are  used,  and  the  execution  of  it  is  not  subject  to  the  delay 
of  getting  rid  of  water  by  slow  and  careful  evaporation,  and 
moreover,  the  varying  strength  of  commercial  muriatic  acid 
may  make  a  difference  in  the  proportions,  if  not  previously 
tested. 
I  have  placed  this  lunar  caustic  in  the  hands  of  a  number  of 
surgeons  and  physicians,  all  of  whom  concede  to  it  valuable 
properties  in  reference  to  its  solidity  and  diminished  solubility. 
It  has  been  in  the  hands  of  Drs.  Miller,  Flint,  Yandell,  Mar- 
shall, and  others  in  this  city ;  Dr.  Pope,  of  St.  Louis  ;  and  Drs. 
Gross  and  Bache,  of  Philadelphia  ;  and  the  reports  from  them 
all  lead  me  to  propose  this  form  of  lunar  caustic  for  general 
adoption.  As  regards  the  exact  per  centage  of  chloride  of  silver 
to  be  used,  this  must  be  left  to  experiment  by  the  surgeons. 
A  very  large  quantity  of  lunar  caustic,  contains  a  greater  or 
less  proportion  of  nitrate  of  potash  or  any  other  cheap  salt,  and 
