TRADE  IN  CINCHONA  BARK  IN  BOLIVIA. 
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milar  character  with  the  balsam,  which  appears  to  me  to  be  due 
to  the  oxidation  of  the  hard  resin,  as  I  have  been  unable  to  ob- 
tain but  a  small  proportion  of  the  blue-colored  oil  when  I  em- 
ployed a  balsam  containing  "soft  resin  "  comparatively  to  when 
I  made  use  of  the  one  above  described,  which,  as  I  have  already 
remarked,  contains  only  "  hard  resin."  A  further  support  of 
this  view  is,  that  pure  essence  of  copaiba  assumes  no  blue  co- 
loration when  distilled  as  above. 
4thly,  That  cold  sulphuric  acid  produces  a  purple  coloration 
with  balsam  of  copaiba,  similar  to  that  obtained  by  its  action  on 
cod-liver  oil.  Such  being  the  case,  it  is  probable  that  a  small 
quantity  of  it,  mixed  with  olive  or  some  other  oil,  may  be  sold 
by  unprincipled  persons  as  genuine  cod-liver  oil  Pharm,  Jour. 
Aug.  1,  1854.  . 
TRADE  IN  CINCHONA  BARK  IN  BOLIVIA. 
By  Dr.  H.  A.  Weddell. 
A  source  of  wealth  in  the  department  of  La  Paz,  quite  as  abun- 
dant as  the  mines,  is  the  trade  in  Cinchona  bark.  The  immense 
importance  that  the  traffic  in  this  production  has  acquired  in  Bo- 
livia, is  a  sufficient  reason  why  I  should  briefly  claim  the  attention 
of  my  readers  to  the  subject,  especially  as  during  my  last  residence 
at  La  Paz,  Cinchona  bark  was  the  chief  subject  of  all  conversation, 
in  consequence  of  the  differences  arising  between  the  bark-cutters 
or  cascarilleros,  and  the  company  which  had  obtained  from  the 
government  the  privilege  of  exporting  this  precious  bark.  It  is 
on  this  point  principally  that  I  will  make  some  remarks. 
As  has  been  stated  by  M.  de  Humboldt,  it  was  not  until  about 
the  year  1776  that  the  Cinchona  barks  of  Lower  Peru  were  offered 
in  the  markets  of  Europe.  Up  to  that  period  these  markets  were 
supplied  almost  exclusively  at  the  expense  of  the  forests  of  Loxa  : 
the  barks  from  New  Granada  appeared  about  the  same  time;  but 
it  was  not  until  much  later  that  the  Cinchona  barks  of  Bolivia,  or 
Higher  Peru,  entered  into  the  competition — a  competition  which 
became  formidable  since  by  the  discovery  in  1820  of  quinine,  the 
febrifuge  principle  par  excellence  of  the  drug,  it  became  manifest 
that  the  Calisaya  bark  far  surpassed  in  richness  all  other  species 
known.    The  forests  of  certain  parts  of  Bolivia  are  in  fact  the 
