RESlNiE  JALAPiE,  P.  B. 
273 
EESINA  JALAPiE,  P.  B. 
By  Mr.  A.  F.  Haselden. 
Whilst  preparing  some  resin  of  jalap  according  to  the  process 
set  down  in  the  British  Pharmacopoeia,  several  points  occurred 
to  me  as  seemingly  worthy  of  consideration  and  inquiry.  The 
mode  of  operating  in  the  B.  P.  is  exhaustion  of  the  root  by 
rectified  spirit,  the  addition  of  a  small  quantity  of  water,  the 
recovery  of  nearly  all  the  spirit  by  distillation,  the  separation 
of  the' resin  from  the  residual  liquor,  subsequent  washing  with 
hot  water,  and  drying  the  resin  with  a  gentle  heat  until  it  be- 
comes brittle,  breaking  with  a  resinous  fracture ;  and  so  far  the 
process  is  all  that  is  necessary  in  order  to  obtain  the  resin  as 
described  in  the  Pharmacopoeia.  The  process  might,  however, 
have  been  carried  further,  and  the  brown  resin  thus  obtained 
rendered  colorless  by  digestion  with  animal  charcoal,  and  thus 
have  represented  pure  resin,  or  the  jalapin  of  commerce.  But 
I  am  far  from  certain  that,  therapeutically,  the  resin  would  have 
been  improved.  I  think  it  quite  possible  that  the  anim'al  char- 
coal does  remove  some  of  the  acrid  principle  upon  which  the 
activity  of  jalap,  as  a  cathartic,  depends  ;  and  I  am  led  to  en- 
tertain this  opinion  from  the  fact  that  I  have  heard  that  jalap- 
in does  not  act  proportionately  as  well  as  good  powdered  jalap- 
root. 
Now,  amongst  other  things  concerning  jalap,  Dr.  Christison 
has  stated  that  worm-eaten  jalap  is  the  best  for  the  preparation 
of  the  resin.  The  late  Dr.  Pereira  apparently  entertained  the 
same  opinion,  for,  in  his  writings,  he  says  jalap-root  is  apt  to 
become  worm  eaten,  the  insects  attacking  the  amylaceous  por- 
tion, leaving  the  resin  ;  hence  worm-eaten  jalap  is  to  be  preferred 
for  the  preparation  of  the  resin.  On  the  other  hand,  Duncan, 
Thornton,  and  Brande  say  that  worm-eaten  jalap  should  be 
rejected.  I  may  probably  be  thought  presuming  when  I  state 
that  I  cannot  entirely  coincide  with  either  side.  Looking  at 
the  manner  in  which  the  resin  is  deposited  in  the  roots,  in 
irregular  concentric  rings,  and  sometimes  seemingly  pervading 
the  whole  mass,  I  could  not  conceive  that  these  worms  or  insects 
could  remove  the  amylaceous  or  extractive  portion,  and  leave 
the  resinous  part  untouched.  I,  therefore,  proceeded  to  extract 
the  resins  from  two  portions  of  jalap-root,  the  one  worm-eaten, 
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