LEAD  AND  ZINC. 
LEAD  AND  ZINC  RESOURCES  OF  THE  UNITED  STATES. 
By  II.  Foster  Bain. 
USES  OF  LEAD  AND  ZINC. 
Lead  and  zinc  are  the  most  important  of  the  base  metals.  In 
value  of  annual  production,  approximately  $45,000,000,  they  rank 
below  gold,  silver,  copper,  and  iron.  They  still  exceed  in  output 
aluminum,  tin,  platinum,  and  several  other  metals  which  per  unit 
ire  more  valuable.  This  intermediate  position  is  mainly  a  reflex  of 
their  intermediate  value  in  the  arts.  Of  low  tenacity,  they  have 
small  value  in  the  form  of  wire  or  beams,  and  hence  can  not  compete 
in  the  main  uses  of  iron  and  steel.  Of  low  electrical  conductivity, 
they  are  shut  out  of  competition  with  copper  in  its  main  field.  Of 
considerable  abundance,  they  have  not  that  element  of  scarceness 
!diich  contributes  to  the  value  of  gold  and  silver.  Despite  these 
nets,  the  two  metals  have  wide  uses,  dependent  in  the  main  upon 
heir  high  malleability  and  their  capacity  to  form  compounds  useful 
s  pigments.  Both  metals  enter  largely  into  the  sheet-metal  trade, 
Did  lead  is  used  in  quantity  for  the  manufacture  of  pipe.  Both 
netals  are,  in  most  situations,  relatively  inert  as  regards  chemical 
mange,  and,  by  virtue  of  this,  lead  is  used  for  lining  acid  tanks  of 
various  kinds,  while  zinc  is  in  high  favor  as  a  roofing  material  and 
for  galvanizing.  Among  the  less  important  uses  for  the  metals  is 
that  of  the  manufacture  of  alloys,  both  readily  forming  such  com- 
binations with  other  metals.  Zinc  enters  largely  into  the  composi- 
ion  of  the  various  brasses  and  friction  metals,  and  lead  is  used  in 
-melting  to  collect  or  alloy  gold  and  silver.  Indeed,  it  is  as  a  by- 
product from  the  smelting  of  the  precious  metals  that  the  bulk  of  the 
ijead  of  commerce  is  derived. 
Within  expanding  limits  it  is  proving  possible  to  substitute  these 
metals,  zinc  in  particular,  for  the  more  expensive  tin  and  copper,  and 
io  a  considerable  extent  because  of  this  fact  there  is  an  active  and 
trowing  demand  for  them  which   warrants  a   brief  review   of  the 
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