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BOGOTA  BARKS  FROM  NEW  GRENADA. 
Pounds  of  arsenic  are  sold  at  the  foregoing  stores  annually,  (and 
it  is  by  far  the  principal  poison  purchased,)  and  professedly  for  the 
destruction  of  rats.  Half  an  ounce  and  an  ounce  are  the  quanti- 
ties generally  bought.  A  few  parcels  of  corrosive  sublimate,  (a 
drachm  or  so  at  a  time,)  are  sold  in  the  course  of  the  year  for 
veterinary  purposes.  No  accident  is  known  to  have  occurred  from 
all  these  sales;  and  but  one  criminal  application  of  poison  during 
the  last  two  or  three  years.  Hence,  a  preparation  (which  I  have 
had  on  hand  for  this  period)  for  the  ready  formation  of  the  hydrated 
peroxide  of  iron,  remains  as  I  first  made  it,  unemployed. 
Thy  friend, 
John  T.  Pltjmmer,  [M.  D.] 
REMARKS  ON  BOGOTA  AND  OTHER  CINCHONA  BARKS  FROM 
NEW  GRENADA,  IN  THEIR  RELATION  TO  THE  MANUFACTURE 
OF  SULPHATE  OF  QUINIA. 
By  William  Procter,  Jr. 
It  is  generally  known  that  the  Cinchonas  valuable  in  medicine 
are  found  on  the  eastern  slopes  of  the  Bolivian,  Peruvian,  and 
New  Grenadan  Andes,  at  a  considerable  elevation,  and  that  at 
least  sixteen  varieties  have  been  found.  It  is  also  equally  well 
known  that  the  Bolivian  bark  called  calisaya  contains  the  largest 
percentage  of  quinia  and  commands  the  highest  price,  and  that 
the  medicinal  value  of  the  other  varieties  is  rated  in  proportion 
to  the  quinia  and  cinchonia  they  contain.  Chemists  have  shown 
that  a  close  relation  exists  between  the  several  alkaloids  that  have 
been  obtained  from  the  cinchonas,  they  being  theoretically  oxides 
of  a  common  radical,  yet  varying  in  the  proportions  yielded  by 
different  species,  and  by  the  same  species  in  different  localities. 
The  cause  of  this  variation  is  an  interesting  question  to  the  ve- 
getable physiologist.  Soil,  elevation,  the  shade  of  associated 
trees,  and  probably  other  causes  are  concerned  in  the  elaboration 
of  these  valuable  constituents,  and  in  determining  their  relative 
and  absolute  proportions. 
Of  the  immense  quantities  of  Bolivian  barks  exported  from 
South  America,  more  than  nine-tenths  are  manufactured  into  sul- 
phate of  quinia.  Knowing  its  superiority  for  this  purpose,  and 
aware  of  the  indispensable  necessity  of  sulphate  of  quinia  to  the 
