234 
ON  SOME  PANAMA  DRUGS. 
not  altered  bj  heat  and  containing  much  iron,  and  of  fine  brown 
and  brown-black  earth.  The  tincture,  measuring  four  ounces,  is 
of  a  yellowish  brown  color,  much  darker  than  tincture  of  myrrh, 
possesses  ah  acid  reaction  and  the  characteristic  odor;  diluted 
until  it  is  almost  colorless,  a  red  color  is  produced  on  the  addi- 
tion of  nitric  acid  ;  if  the  tincture  is  mixed  with  water  it  becomes 
milk-white,  and  the  addition  of  nitric  acid  now  produces  a  rose 
color  which  is  very  permanent.  That  tincture  of  myrrh  is 
colored  red  by  nitric  acid  is  well  known ;  if  the  acid  is  added 
after  the  previous  addition  of  water,  nitric  acid  produces  a 
similar  color  ;  on  standing  for  some  time  a  brqwn  precipitate  is 
separated  and  the  turbid  supernatant  liquid  assumes  arose  color. 
The  tincture  slowly  reddens  blue  litmus  paper  and  on  evapora- 
tion leaves  a  resinous  mass  of  a  ruby  brown  color,  perfectly 
transparent,  readily  fusible  and  soon  becoming  brittle  on  ex- 
posure. This  residue  dissolves  readily  and  completely  in  alco- 
hol, ether,  chloroform  and  oil  of  turpentine,  and  is  partly  soluble 
in  caustic  alkalies,  to  a  larger  extent  in  the  fixed  alkalies  than 
in  ammonia. 
Caranna,  when  continually  triturated  with  water,  is  to  a  small 
extent  disintegrated  and  forms  an  incomplete  emulsion,  which 
soon  deposits  all  the  resinous  matter. 
J'rom  its  properties  and  behaviour  it  admits  hardly  of  any 
doubt  but  that  the  caranna  of  Panama  originates  from  a  tree 
belonging  to  the  natural  order  of  Terebinthacese,  but  the  genus 
and  species  from  which  it  is  derived  is  not  clearly  established  yet. 
It  is  mentioned  above  that  Hancock  refers  this  oleoresin  to 
the  Aniba  of  Aublet ;  but  this  author,  who  always  records  very 
carefully  the  exudations  of  the  trees,  omits  to  state  in  this  case 
that  the  aniba  yields  an  exudation  ;  he  simply  says  :  "  Lignum 
trunci  aromaticum  citrinum  ;"  and  it  is  scarcely  probable  that  this 
tree  should  yield  the  caranna  and  he  not  have  been  informed  of 
the  fact,  while  he  carefully  records  many  facts  connected  with 
the  wood.* 
*  Get  arbre  est  appele  Bois  de  Cedre  par  les  habitans  du  comte  de 
Gene.  On  en  travaille  le  bois  pour  faire  des  piroques,  et  lis  pretendent 
que  le  tronc  pourrait  servir  a  faire  des  mats  de  navire. — Histoire  des 
plantes  de  la  Guiane  francaise.  Par  M.  Fusee  AuNet,  1775.  Tom.  I.  p. 
328. 
