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CHLORINATED  LUNAR  CAUSTIC. 
as  this  often  falls  into  the  hands  of  physicians  when  they  desire 
the  pure  article,  it  is  well  to  have  a  ready  and  simple  test  that 
every  physician  may  apply.  The  following  one,  proposed  by 
Dr.  Ed.  R.  Squibb,  answers  the  purpose  perfectly  well : 
"  A.  small  fragment  of  nitrate  of  silver,  crushed  to  powder  with 
a  knife-blade  upon  a  piece  of  paper,  the  powder  spread  out  over 
the  paper,  and  the  paper  and  powder  then  rolled  up  in  a  small 
match-like  roll,  twisted,  set  on  fire,  and  burned,  leaves  a  tasteless 
residue  of  pure  silver.  But  if  the  nitrate  of  silver  contains  even 
one  per  cent,  of  any  saline  impurity,  the  residue,  instead  of  be- 
ing tasteless,  will  have  the  sharp  alkaline  taste  of  the  base  of  the 
adulterating  salt.  With  this  test,  no  one  need  be  deceived  by 
No.  2  lunar  caustic,  nor  by  the  adulteration  of  the  crystallized 
nitrate  with  chlorate  of  potash,  &c;  and  even  the  small  pro- 
portion of  sal  prunelle  that  is  often  added  to  the  so-called  pure 
or  "  No.  1  caustic  "  to  make  it  run  well,  is  detected  in  a  minute 
with  equal  certainty.  This  test  answers  equally  well  for  the 
purity  of  the  chlorinated  lunar  caustic." 
Instead  of  crushing  the  lunar  caustic  on  a  piece  of  paper, 
wrapping  and  then  burning,  I  have  found  it  preferable  to  dis- 
solve it  in  a  little  water,  moisten  a  piece  of  paper  with  the  solu- 
tion, dry  it,  roll  the  paper  up  and  burn.  By  this  modification 
I  have  never  failed  to  produce  complete  decomposition,  whereas 
in  manipulating  the  lunar  caustic  as  prepared  by  Dr.  Squibb,  I 
have  failed  more  than  once  to  produce  a  complete  decomposi- 
tion, and  upon  tasting  the  residue,  found  undecomposed  nitrate 
of  silver. 
With  these  facts  before  them,  physicians  need  never  be  de- 
ceived with  impure  lunar  caustic. — Louisville  Seminary  Month- 
ly Medical  News,  Feb.  1,  1859. 
