ON  THE  RESINOIDS. 
303 
not  liquifiable  by  heat,  and  differ  somewhat  in  other  respects  from 
the  pure  resins,  they  are  termed  Resinoids." 
Many  of  them  may  be  obtained  by  the  following  simple  process  : 
form  a  saturated  tincture  of  the  root  or  plant  desired,  which  is 
best  done  by  displacement,  or  by  macerating  the  ground  mate- 
rial in  strong  alcohol,  and  expressing  ;  from  this  tincture  distil  or 
evaporate  off  the  alcohol,  having  previously  added  plenty  of 
water  ;  the  alcohol,  which  held  the  resin  in  solution,  being  thus 
removed,  and  the  resin  not  being  soluble  in  water,  it  is  precip- 
itated, while  the  other  substances  which  the  alcohol  had  dissolved 
out,  as  the  extractive  and  coloring  matter,  being  also  soluble  in 
water,  are  held  in  solution  by  the  water,  and  thus  separated  from 
the  resinoid. 
The  precipitate  was  then  collected  and  purified  by  frequent 
washing,  or  by  being  redissolved  in  alcohol  and  again  precipitated, 
and  was  then  dried  and  powdered  for  use. 
Thus  may  be  prepared  the  resinoids,  Podophyllin,  Cimicifugin, 
Leptandrin,  Helleborin,  Sanguinarin,  Caulophyllin,  and  nu- 
merous others,  experimented  on,  but  not  above  mentioned. 
By  the  above  process,  the  resinoid  is  not  obtained  in  its  chemi- 
cally pure  state ;  it  probably  contains  from  two  and  a  half  to 
five  per  cent  of  coloring  matter  and  extractive,  which,  however, 
does  not  sensibly  affect  its  use  as  a  medicine  :  while  a  further 
purification  would  not  only  add  to  its  cost,  but  might  even  en- 
danger its  activity.  Its  complete  purification  must  be  effected  by 
redissolving  it  in  alcohol,  digesting  the  solution  with  animal  char- 
coal, filtering,  and  again  precipitating  by  water. 
Perhaps  these  investigations  have  been  more  extended  than 
the  importance  of  the  subject  may  appear  to  warrant ;  but  this 
subject  of  the  Resinoids  under  consideration  is  one  of  those  of 
which  the  apothecaries  have  but  little  knowledge  and  it  may 
be  an  inducement  for  other  experimenters  to  take  hold  of  the 
above,  and  go  more  fully  into  the  subject. 
[Note. — The  author's  remark  at  page  301,  that  but  little  light  has  been 
thrown  on  the  subject  of  Podophyllum  since  1832,  is  certainly  incorrect, 
inasmuch  as  the  resinous  nature  of  the  active  principle  was  ascertained 
by  Lewis,  in  1846.  Whatever  relation  the  product  of  Mr.  Hodgson's 
formula  bears  to  the  resin  of  Lewis,  or  the  crude  resinoid  of  commerce,  it 
probably  either  owes  its  activity  to  that  principle,  rendered  soluble  by  aid 
of  associated  substances  in  the  water  of  the  decoction,  or  is  a  modified 
form  of  the  resinoid. —EoiToii  Amer.  Journ.  Piiarm.] 
