HESS 
GE 
vYu.v"]  OCCURKENCE    AND    DISTRIBUTION    OF    TIN.  175 
by  HUM),  a  man  being  able  to  make  two  trips  a  day,  carrying  75  pounds 
at  a  load.  At  this  depth  there  were  still  5,000  tons  of  25  per  cent  ore 
in  sight.  The  development  of  the  mines  has  been  very  slow  on  ac- 
count of  the  lack  of  transportation  facilities,  everything  having  to  be 
moved  by  pack  mules  or  llamas.  The  building  of  the  Antofagasta 
and  Oruro  Railroad  has  made  a  great  difference,  but  many  mines 
are  still  90  miles  or  more  from  the  railroad. 
There  is  no  coal  in  this  part  of  the  country  and  little  wood,  the  only 
fuel  being  llama  dung,  and  this  is  getting  scarce.  Gas  engines  and 
petroleum  engines  are  therefore  being  installed. 
Water  is  scarce  in  many  places  and  aerial  trams  are  being  installed 
to  move  the  ore  to  points  nearer  water  and  more  convenient  for 
milling.  One  of  these  aerial  trams  is  nearly  2  miles  long,  and  it 
has  reduced  the  cost  of  transporting  the  ore  to  about  one-tenth  its 
former  cost,  from  $1.25  per  ton  mile  to  10  cents  per  ton  mile. 
Modern  stamps  have  been  set  up  in  many  places,  but  in  others  ore 
is  crushed  by  Chilian  mills,  and  in  places  a  rocking-stone  is  still  used. 
Ball,  roll,  and  Huntington  mills  are  also  used. 
Jigs,  classifiers,  buddies,  and  Frue  vanners  are  used  in  concentrat- 
ing the  ores,  but  in  some  places  they  are  still  concentrated  by  hand 
in  shallow  streams  of  water. 
Much  of  the  "  barilla,"  or  tin  concentrates,  is  shipped  to  Europe  for 
smelting,  the  larger  part  going  to  London.  A  small  portion  only  is 
smelted  in  the  country. 
Tin  placers,  called  "  veneros,"  occur  at  a  number  of  places — Ocuri, 
Japo,  Huanuni,  and  elsewhere — but  their  importance  is  not  great  as 
compared  with  the  lode  mines. 
The  production  of  tin  in  Bolivia  for  the  year  1904  was  about 
10,300  tons. 
With  improvement  in  transportation  facilities  there  will  probably 
be  a  considerable  increase  in  the  output  of  tin. 
Chile. — A  few  tons  of  tin  ore  per  year  are  produced  in  Chile,  but 
the  output  is  unimportant.     In  1901,  4  tons  of  tin  were  gotten  out. 
EUROPE. 
In  the  European  region  England  has  produced  and  still  produces 
much  more  tin  than  the  rest  of  Europe  combined.  Spain,  Portugal. 
France,  Germany,  Austria,  Italy,  and  Russia  produce  small  quan- 
tities. 
England.— Tin  has  been  mined  in  England  for  at  least  two  thou- 
sand years  and  probably  much  longer.  The  mines  of  Cornwall,  in 
the  southwest  part  of  England,  are  at  present  practically  the  only 
English  producers. 
