AmkiTcrh,Sym'}       Action  of  Hydrogen  Peroxide.  123 
All  the  specimens  were  free  from  resin  of  guaiac,  as  was  indicated 
by  not  obtaining  a  blue  color  when  the  alcoholic  solution  was  added 
to  the  fresh-cut  surface  of  a  potato. 
Resin  or  colophony  was  sought  for  by  the  addition  of  sulphuric 
acid,  which  should  give  a  red  color  immediately  on  adding  to  the 
resin.  There  was  no  immediate  change  produced  with  No.  1,  but 
with  Nos.  2  and  3,  the  acid  produced  immediately  a  dark  reddish- 
brown  color.  Negative  tests  were  also  obtained  for  calcium  carbo- 
nate. The  ash  of  specimen  No.  1  was  0-8  per  cent.;  of  No.  2,  0-6 
per  cent.,  and  of  No.  3,  0-6  per  cent. 
The  conclusions  from  this  investigation  are  that  a  resin  of  scam- 
mony  may  be  obtained  in  this  market  which  meets  all  the  tests  of 
the  Pharmacopoeia,  but  that  the  most  of  that  used  does  not  fully 
comply  with  the  requirements  of  our  national  standard. 
THE  ACTION   OF   HYDROGEN   PEROXIDE  UPON 
METALLIC  SALTS. 
By  Frank  X.  Moerk,  Ph.G. 
Contribution  from  the  Chemical  Laboratory  of  the  Philadelphia  College  of  Pharmacy. 
No.  103. 
Read  at  the  Pharmaceutical  Meeting,  February  16,  1892. 
The  prescription  submitted  at  one  of  the  recent  Pharmaceutical 
Meetings,  led  me  to  make  some  experiments  to  ascertain  the  reaction 
taking  place,  and  later  to  extend  the  investigation  so  as  to  embrace 
the  above  title.  The  prescription  in  question  was  as  follows  :  Tr. 
Ferri  chlorid.,  f^ss  (2  cc.);  glycerin.,  f 3  ij  (8  cc.).;  hydrogen,  peroxid. 
f^vi  (24  cc).  The  materials  were  mixed  in  a  two-ounce  bottle  and 
then  tightly  stoppered  with  a  perforated  cork,  through  which  was 
inserted  a  thermometer  (this  experiment  was  made  after  a  prelimi- 
nary experiment  proved  it  to  be  entirely  safe) ;  there  was  noticed  an 
immediate  deepening  of  the  color  after  mixing ;  starting  with  an 
initial  temperature  of  290  C,  the  heat  developed  was  recorded  at 
intervals,  the  thermometer  indicating  after  5  minutes  330  C,  after  10 
minutes,  390  C,  after  15  min.,  540  C,  after  18  min.,  64 0  C,  and 
then  the  temperature  decreased  until  after  75  minutes  the  initial 
temperature  was  again  recorded  ;  the  color  had  changed  to  a  light 
yellow;  upon  removing  the  stopper  it  was  found  that  no  pressure 
existed  in  the  bottle,  but  that  there  was  a  pronounced  odor  of 
