Ami£gusMKm'}     Notes  on  Some  Saps  and  Secretions.  415 
large  iron  pots.  After  this  the  rags  are  subjected,  while  still  hot, 
to  great  pressure  in  an  Indian  machine  made  of  strong  ropes  and 
wooden  levers  worked  by  hand.  The  balsam  oozes  out  and  falls 
into  a  receptacle,  where  it  is  allowed  to  cool.  This  is  called  raw 
balsam.  To  refine  it  they  boil  it  again  and  drain  it,  after  which 
they  pack  it  in  iron  cans  ready  for  market.  The  other  method 
of  extracting  balsam  consists  in  entirely  barking  the  trunk  and 
heavy  branches  of  the  tree,  a  process  which,  as  a  rule,  kills  it  out- 
right, and  at  best  renders  it  useless  for  several  years.  The  bark  is 
finely  ground,  boiled  and  submitted  to  pressure  in  order  to  extract 
the  oil,  which  is  considered  of  an  inferior  quality  to  that  obtained  by 
the  system  first  described.  Both  methods  are  defective,  but  the 
latter  is  ruinous,  and  is  forbidden  by  the  authorities.  The  name  of 
"  Peruvian  balsam  "  was  given  to  this  article  because  it  was  first 
sent  from  Salvador  to  Peru,  in  the  time  of  the  Spaniards,  and  from 
Callao  reshipped  to  England. 
About  6,000  pounds  of  the  balsam  go  to  the  United  States 
annually.  Thirty  years  ago,  many  thousand  pounds  of  it  were 
received  in  England,  but  the  imports  there  rarely  exceed  now  2,000 
pounds.  It  is  a  warm  and  stimulating  tonic  and  expectorant,  useful 
in  chronic  catarrh,  asthma  and  other  pectoral  complaints  and 
rheumatism.  Externally  it  is  much  used  in  Europe,  in  the  treat- 
ment of  scabies,  as  being  equally  effective,  and  more  agreeable  than 
sulphur  in  its  application. 
The  balsams  of  Tolu  and  Peru  are  employed  occasionally  medi- 
cinally in  the  state  of  syrup  or  tincture,  particularly  in  cough 
mixtures;  their  fragrance  also  renders  them  pleasant  adjuncts  to 
chocolate,  liqueurs  and  other  articles. 
Balsam  of  Peru  is  seldom  met  with  in  commerce  unadulterated. 
The  best  test  is  its  specific  gravity,  which  ought  to  be  between  1-14 
and  ri6.  The  difficulty  of  taking  the  specific  gravity  is  best  over- 
come by  making  a  solution  of  one  part  of  chloride  of  sodium  in 
five  parts  of  water,  the  specific  gravity  of  which  is  1-125.  In  this 
liquor  a  drop  of  Peru  balsam,  if  pure,  ought  to  sink  down.  (Other 
tests  were  given  in  Vol.  66,  p  100.) 
Uncaria  Gambir,  Roxb.  Nanclea  Gambir,  Hunter. — This  plant 
yields  the  extract  known  as  pale  catechu  in  pharmacy,  which  is 
largely  imported  into  Europe  from  Singapore,  under  the  commercial 
name  of  Gambier,  and  frequently  under  the  old  erroneous  designa- 
