252 
Syrup  of  Acacia, 
Am.  Jour.  Pharm. 
June,  1875. 
escape,  then  cover  it  with  another  watch-glass  exactly  fitting  the  firsts 
and  drive  the  iodine  into  this  by  increasing  the  heat  j  the  difference  in 
weight  gives  the  amount  of  water. 
After  this  preliminary  proceeding,  put  into  a  glass-stoppered  bottle 
the  full  quantity  of  iodine,  a  surplus  of  iron,  best  in  the  shape  of  small 
French  nails  or  fine  wire,  water  sufficient  to  make,  with  double  the 
weight  of  sugar,  the  exact  volume  of  syrup.  Expose  the  bottle  to  a 
gentle  heat  until  the  iodine  is  combined,  filter  when  cold,  and  make 
the  syrup  by  gently  heating  the  solution  with  the  sugar.  If  time  is 
given,  the  heating  is  unnecessary,  as  an  occasional  shaking  of  the  bottle 
is  sufficient  to  bring  on  the  chemical  combination  between  the  iodine 
and  the  iron. 
The  quantity  of  sugar  of  the  officinal  formula  is  insufficient ;  the 
syrup  will  keep  better  when  thicker,  though  even  then  it  is  liable  to  the 
same  decomposition,  but  slower  than  the  aqueous  solution.  As  a  pre- 
ventative, Mr.  Mayer  recommends  sodium  hyposulphite  ;  this  is  surely 
of  all  known  remedies  the  best,  but  he  decomposes  it  by  iodine,  and  so 
converts  it  into  sodium  iodide  and  sodium  tetrathionate.  A  solution  of 
ferrous  iodide,  prepared  by  his  formula,  separated  ferric  oxide  in  twenty- 
four  hours.  But  when  a  small  quantity  of  sodium  hvposulphite  was 
added  to  the  fresh  syrup,  it  kept  its  greenish  color  well  for  months. 
Experiments  which  I  made  with  a  browned  syrup  to  restore  the  color 
by  iodine  and  heat,  as  found  by  Mr.  Mayer,  were  not  successful,  though 
some  iodine  escaped  with  the  vapors.  A  dark  syrup  exposed  to  the 
rays  of  the  sun  turned  greenish  by  the  conversion  of  the  free  iodine  into 
HI.* 
SYRUP  OF  ACACIA. 
BY   C.   B.   MANN,   OLYMPIA,  W.  T. 
Syrup  of  gum  arable  prepared  by  the  officinal  formula  is,  as  Mr» 
Rother  remarks  of  the  mucilage,  remarkable  for  its  instability  ;  yet  its 
superior  adaptability  as  a  demulcent,  and,  many  times  in  the  prepara- 
tion of  pills,  troches  and  mixtures,  make  it  a  very  desirable  prepara- 
tion. However,  in  localities,  and  at  times  when  business  in  the  pre- 
scription department  is  slack,  we  frequently  turn  to  our  syrup  bottle  only 
to  find  its  contents  sour. 
Some  time  since,  while  reading  an  article  by  Mr.  Rother,  on  muci- 
*  Compare  also  papers  on  the  same  subject  published  In  "American  Journal  of 
Pharmacy,"  1854  and  1855. — Editor. 
