1.  Where  a  contract  is  clear  and  certain  in  its  terms  and  meaning,  and

there  is  no  latent  ambiguity  necessitating  proof  of  a  custom  to  in-
terpret its  meaning,  its  construction  is  for  the  Court  and  not  for
■  the  jury.
2.  Where  a  contract  between  a  mining  company  and  a  smelting  company

provided  that  the  latter  was  to  smelt  ore  for  the  former  at  $10  per
ton  and  to  pay  to  the  former  95  per  cent,  of  the  silver  produced,
and  by  another  clause  it  was  provided  that  the  95  per  cent,  of  sil-
ver **  produced  from  the  ore  as  aforesaid"  should  rtot  be  demand-
ed until  a  certain  time;  and  on  the  trial  of  an  action  for  monev
due  the  mining  company  under  the  contract,  the  plaintiff  mining
company  contended  that  the  ores  were  to  be  paid  for  at  their  assay
value  according  to  a  custom  among  smelters,  and  not  on  the  basis
of  the  silver  produced  by  the  smelting  process;  Heldy  that  the  con-
tract was  not  ambiguous  in  its  terms,  and,  therefore,  should  be
construed  by  the  Court,  and  it  was  error  to  submit  to  the  jury  the
question  whether  the  alleged  custom  existed  among  smelters.
3.  Where,  in  the  trial  of  an  action  in  which  several  issues  have  been

submitted  and  responded  to,  an  erroneous  instruction  was  given
upon  one  issue  entirely  distinct  and  separable  from  the  other  is-
sues and  matters  involved  in  the  case,  and  a  new  trial  can  be  had
upon  such  issue  alone  without  danger  of  complication,  the  new
trial  will  be  confined  to  such  issue.
