ON  MYROXYLON  TOLUIFERUM,  ETC. 
449 
cess  was  conducted  strictly  according  to  the  Pharmacopoeia, 
the  first  ten  fluid  drachms  being  rejected,  and  then  the  product 
collected  until  one  fluid  ounce  was  left  in  the  retort. 
The  distillate  in  this  case  was  free  from  any  smell  of  sul- 
phurous acid.  Its  specific  gravity  was  1843.  One  fluid  drachm 
(100'8  grains)  of  this  acid  was  neutralized  by  202  measures  of 
the  volumetric  solution  of  soda,  indicating  that  it  contained 
more  than  one  atom  of  water  to  the  atom  of  anhydrous  acid. — 
London  Pharm.  Joum.,  June  1,  1864. 
ON  MYROXYLON  TOLUIFERUM,  AND  THE  MODE  OF  PRO- 
CURING THE  BALSAM  OF  TOLU. 
By  John  Weir. 
Extracted  from  the  Proceedings  of  the  Royal  Horticultural  Society  for  May,  1864. 
[Previous  to  his  departure  for  New  Grenada,  Mr.  Weir  re- 
ceived instructions  to  make  inquiries  respecting  certain  interest- 
ing medicinal  plants  growing  in  that  country,  especially  the 
Balsam  of  Tolu  tree  and  Sarsaparilla,  and  to  obtain,  if  possi- 
ble, seeds  and  specimens.  In  accordance  with  these  instruc- 
tions, Mr.  Weir  has  communicated  the  following  interesting 
notice  of  his  proceedings.] 
From  inquiries  made  during  the  voyage  out,  and  immediately 
on  landing  in  this  country,  1  learn  that  a  good  deal  of  the  Bal- 
sam of  Tolu  was  brought  down  the  river  Magdalena  annually 
to  Barranquilla,  whence  it  is  exported  to  Europe.  I  therefore 
thought  that  the  best  way  of  reaching  the  country  where  the 
tree  grows,  was  to  go  up  the  river  to  one  of  the  ports  1  was 
informed  the  drug  came  from,  where  I  hoped  to  be  able  to  pro- 
cure specimens  and  collect  the  desired  information  concerning 
it.  At  all  events,  I  was  told  that  by  going  to  one  of  the  ports 
on  the  lower  Magdalena,  I  could  cross  the  country  to  the  valley 
of  the  Zinu  quite  as  easily  as  I  could  reach  the  mouth  of  that 
river  from  Cartagena  by  sea. 
Following  up  this  plan,  I  took  a  passage  to  Mompox  by  the 
first  steamer  up  the  river,  after  my  arrival  at  Barranquilla.  On 
arriving  at  Mompox,  I  found  that  no  balsam  was  gathered  there 
(although  I  had  been  assured  to  the  contrary  in  Barranquilla), 
and  that  the  people  generally  did  not  know  the  tree-  a  negro 
29 
