100 
SYRUPUS  FERRI  IODIDI. 
iodine.  Dusty  bottles,  the  use  of  corks  instead  of  glass  stop- 
pers, and  many  other  such  apparently  trivial  matters  will  often 
start  or  favor  this  change,  though  no  such  causes  can  be  found  in 
the  instance  referred  to. 
In  estimating  the  amount  of  iodine  liberated  in  this  change  it 
was  found  to  be  exceedingly  small,  and  practically  quite  insignifi- 
cant, even  in  those  bottles  which  were  of  the  deepest  color. 
No  deposite  had  occurred  in  any  of  the  bottles,  however,  and  it 
is  doubted  whether  a  deposit  ever  occurs. in  any  well  managed 
preparation  made  by  any  of  the  later  processes:  It  having  been 
thus  shown  that  the  medicinal  properties  were  not  materially 
impaired  by  this  change,  since  the  amount  of  free  iodine  was  too 
minute  to  produce  any  effect  even  upon  the  most  delicate  con- 
dition, a  remedy  for  the  discoloration  was  sought  for  upon 
chemical  principles,  and  was  soon  found  in  the  hyposulphite  of 
soda,  and  it  is  the  object  of  this  note  to  publish  a  method  of 
using  the  remedy.-  A  solution  of  fifteen  or  twenty  grains  of 
crystallized  hyposulphite  of  soda  in  one  fluidounce  of  water  is 
strong  enough  for  the  purpose,  and  from  fifteen  to  twenty  minims 
of  this  solution  is  sufficient  for  each  pound  of  the  syrup  when 
the  latter  is  not  of  a  darker  color  than  brown  sherry  wine.  When 
darker  than  this,  double  the  quantity  is  required.  The  solution 
is  simply  added  to  the  discolored  syrup  in  the  bottles  and  shaken 
up  at  ordinary  temperatures.  Syrup  so  restored  is  afterward 
much  less  susceptible  to  the  change,  and  the  writer  has  now  a 
specimen  which  has  been  freely  exposed  to  the  air  in  a  gradu- 
ated measure  for  four  weeks  or  more,  without  any  appearance  of 
change  even  on  the  surface.  The  quantity  of  the  solution  re- 
quired to  restore  the  syrup  is  a  measure  of  the  amount  of  change 
which  may  have  taken  place.  The  restored  syrup  is  not  of  the 
full  original  green  color,  but  rather  more  inclined  to  olive 
or  a  very  pale  brown,  and  is  not  quite  as  transparent.  This 
latter  is  probably  due  to  the  precipitation  of  a  minute  quantity 
of  finely  divided  sulphur. 
This  remedy  having  succeeded  in  one  single  instance,  is  con- 
sidered reliable  only  so  far  as  its  chemical  principles  are  con- 
cerned, and  is  only  published  in  order  that  its  applicability  may 
be  tested ;  and  the  writer  suggests  to  those  interested  in  the 
