i^ptembe^™'}     The  Apocynacece  in  Materia  Medica.  449 
the  hide  powder  with  water,  allows  it  to  swell  about  twenty  hours, 
and  expresses  the  water  through  a  wetted  linen  cloth.  The  moist- 
ened powder  is  then  put  into  a  glass  flask  holding  150  cubic  centi- 
metres, and  50  cubic  centimetres  of  the  decoction  added,  the  whole 
vigorously  shaken  and  allowed  to  stand  from  ten  to  twenty 
hours,  with  occasional  shaking.  It  is  then  to  be  poured  upon  a  dry 
filter,  and  of  the  filtrate  10  cubic  centimetres  are  to  be  taken  for 
the  titration. 
Of  the  isinglass  as  prepared  by  the  writer,  1  gram  appears  to  be 
sufficient  for  detannating  50  cubic  centimetres  of  the  decoction. 
The  isinglass  is  added  to  50  cubic  centimetres  of  water  contained 
in  a  flask  of  150  cubic  centimetres  capacity,  allowed  to  swell  about 
fifteen  minutes,  and  vigorously  shaken.  The  violent  agitation 
causes  the  isinglass  to  break  up  into  a  pulpy  condition.  It  is  then 
to  be  transferred  to  a  muslin  strainer,  and  as  much  water  as  possible 
squeezed  out.  The  moist  mass  of  isinglass  is  then  transferred  to 
the  flask  containing  50  cubic  centimetres  of  the  decoction  of  oak 
bark,  and  the  whole  well  shaken  for  about  fifteen  minutes,  when  the 
decoction  will  be  found  to  be  detannated  and  ready ;  when  filtered 
for  titration,  it  will  be  seen  that  whilst  by  the  use  of  hide  powder 
it  will  require  twenty  hours  to  swell  it,  and  twenty  hours  more  to 
absorb  the  tannic  acid,  the  same  results  will  be  obtained  by  the  use 
of  the  isinglass  in  about  half  an  hour.  Prepared  isinglass  is,  there- 
fore, to  be  preferred,  not  only  on  account  of  the  facility  with  which 
it  is  prepared  and  the  expeditious  way  in  which  it  absorbs  tannic 
acid,  but  also  its  cheapness. 
THE  APOCYNACEyE  IN  MATERIA  MEDICA.1  — 
By  George  m.  Beringer. 
GENERAL  KNOWLEDGE  OF  THE  FAMILY. 
Morphology. — Very  rarely  herbaceous  and  in  all  cases  perennial 
plants,  the  Apocynaceae  are  trees,  shrubs  or  woody  climbers,  and  in 
1  The  material  in  this  paper  is  abstracted  from  that  valuable  monograph 
recently  issued,  entitled  "  Produits  Fournis  a  la  Matiere  Medicate  par  la  Fam- 
ille  des  Apocynees,  par  Louis  Planchon,  Docteur  en  Medecine,  Licencie  es 
Sciences  Naturelles,  Pharmacien  Superieur,  Charge  du  Cours  de  Matiere  Medi- 
cale  a  L'Ecole  Superieurede  Pharmacie  de  Montpelier,  Membre  Correspondant 
