Am.  Jour.  Peiarm.  > 
June  1, 1873.  j 
Flowers  of  Solidago  Bicolor. 
25a 
protoiodide.  As  the  new  salt  contains  about  42  per  cent,  of  iodine 
and  9  per  cent,  of  metallic  iron,  this  shows  that  its  effects  are  pro- 
portionally greater  than  those  obtained  from  the  same  substances 
administered  as  protoiodide. 
Its  medical  properties  are,  otherwise,  precisely  the  same  as  those- 
of  the  officinal  iodide  of  iron,  and  its  administration  has  always  been 
followed  by  the  most  gratifying  results  ;  but  it  is  not  my  province  to 
speak  of  this,  except  to  mention  that  it  has  found  great  favor  among 
children  and  female  patients,  on  account  of  its  relatively  pleasant 
taste  and  because  it  never  blackens  their  teeth. 
Much  of  this  applies  also  to  the  tasteless  tincture  of  muriate  of 
iron.  The  officinal  tincture  is  still  more  injurious  to  the  teeth  than 
the  syrup  of  protoiodide  of  iron;  it  not  merely  blackens  them,  but 
destroys  them  when  used  long  enough.  I  have  heard  some  dentists 
speak  very  strongly  on  the  subject.  The  tincture  I  send  you  con- 
tains the  same  proportion  of  iron  as  the  tinct.  ferri  sesquichloridi^ 
U.  S.  P.  I  left  the  dose  the  same  as  that  of  the  officinal  prepara- 
tion, but  I  have  no  doubt  that  experiments  now  being  made  will  war- 
rant a  reduction  in  the  dose. 
In  regard  to  the  quantity  of  citric  acid  needed  for  one  fluid-ounce 
of  tincture  of  muriate  of  iron,  I  have  found  from  recent  experiments 
that  it  requires  from  90  to  95  grains  of  citric  acid  neutralized  by  180 
to  190  grains  of  crystallized  carbonate  of  soda  to  transform  that 
quantity  into  the  tasteless  compound.  It  seems  singular  at  first  sight 
that  the  more  acid  is  the  solution  of  muriate  of  iron,  the  more  citric 
acid  it  requires ;  but  it  is  easy  to  account  for  that  apparent  anomaly : 
for,  any  excess  of  muriatic  acid  decomposing  a  corresponding  quan- 
tity of  citrate  of  soda,  more  of  that  salt  is  needed  in  proportion  to 
the  free  acid  present. 
J.  Creuse. 
New  York,  May  20,  1873. 
ON  THE  FLOWERS  OF  SOLIDAGO  BICOLOR. 
By  Adam  Conrath. 
From  an  Inaugural  Essay. 
The  flowers  which  were  used  for  the  experiments  hereafter  to  be 
noticed  were  collected  in  the  vicinity  of  Germantown  in  the  forepart 
