Am.  Jour.  Pharm.  ) 
March  1,  1872.  j 
Mucilage  of  Acacia. 
113 
MUCILAGE  OF  ACACIA. 
By  R.  Rother. 
Mucilage  of  gum  arabic  prepared  by  the  officinal  method  is  remark- 
able for  its  instability  ;  only  a  few  days,  and  under  peculiar  condi- 
tions a. few  hours,  sufficing  to  render  it  sour  and  consequently  unfit 
for  medicinal  use.  Mucilage  for  medicinal  purposes  is  an  article  of 
great  utility  to  the  pharmaceutist  in  the  making  of  pills,  emulsions, 
and  other  mixtures  with  which  gum  is  prescribed.  For  these  pur- 
poses it  is  always  far  superior  to  the  powdered  gum.  But  on  every 
occasion  it  should  either  be  quite  recently  prepared  or  otherwise  pre- 
served from  change.  The  moderately  circumstantial  and  rather  tedi- 
ous operation  of  dissolving  the  gum  when  in  the  original  pieces  debars 
the  possibility  of  an  expeditious  process  for  extemporaneous  applica- 
tion. In  view  of  these  facts,  the  addition  of  the  least  objectionable 
preservative  can  only  meet  with  approval.  Glycerin  has  been  recom-. 
mended  and  used  for  nearly  everything,  and  there  exists  not  the 
slightest  doubt  but  that  it  enters  largely  into  pharmaceutical  produc- 
tions. Now  while  glycerin  may  be  positively  injurious  in  some  cases, 
it  has  become  actually  indispensable  for  others.  Too  frequently  it  is 
introduced  where  there  is  no  cause  for  its  presence,  and  often  where 
its  influence  would  be  beneficial,  the  proportion  was  not  sufficient  to 
be  effective. 
The  decomposition  of  mucilage  of  acacia  when  once  begun  cannot 
be  checked  or  even  retarded  with  glycerin,  but  can  be  prevented  by 
a  sufficiency  of  glycerin,  if  this  be  present  before  any  change  could  su- 
pervene. This  is  only  secured  by  mixing  the  glycerin  with  the  water  be- 
fore its  addition  to  the  gum.  Next  important  to  the  solvent  is  the  man- 
ner in  which  the  solution  of  the  gum  is  effected.  This  operation  can  be 
most  promptly  and  thoroughly  performed  b}^  placing  the  original 
pieces  of  the  gum  into  an  appropriately  sized  bottle,  and  adding  the 
mixture  of  glycerin  and  water.  The  bottle  is  then  securely  corked, 
the  whole  well  shaken,  and  the  bottle  laid  down  on  its  side  in  a  hori- 
zontal position  ;  after  10  or  15  minutes  the  layer  of  agglutinated  gum 
is  moved  into  a  vertical  position  by  revolving  the  bottle  ;  after  the  col- 
umn has  subsided,  the  bottle  is  farther  revolved  in  the  same  direction. 
Having  thus  moved  the  bottle  three  or  four  times  during  the  interval 
of  about  twelve  hours,  complete  solution  has  taken  place.  The  muci- 
lage is  now  well  shaken  and  strained  through  muslin.  The  straining 
can  be  very  rapidly  done  by  placing  a  proportionately  large  sheet  of 
