But  the  expansion  of  old  trades  and  the  growth  of
new  trades  have  long  tended  to  outgrow  the  capitals
that  can  easily  be  obtained  by  private  companies;
and  from  the  end  of  the  Middle  Ages  to  the  present
time  there  has  been  a  movement  of  constantly  in-
creasing force  towards  the  substitution  of  public
joint  stock  companies,  the  shares  of  which  can  be
sold  to  anybody  in  the  open  market,  for  private
companies,  the  shares  in  which  are  not  transferable
without  the  leave  of  all  concerned;  and  various
plans,  with  which  we  need  not  occupy  ourselves
just  now,  have  been  adopted  in  different  countries
for  enabling  the  shareholders  to  limit  their  risks  to
their  shares.  The  effect  of  this  change  has  been  to
induce  people,  many  of  whom  have  no  special
knowledge  of  trade,  to  give  their  capital  into  the
hands  of  others  employed  by  them:  and  there  has
thus  arisen  a  new  distribution  of  the  various  parts
of  the  work  of  business  management.
The  ultimate  undertakers  of  the  risks  incurred  by
a  joint  stock  company  are  the  shareholders;  but  as  a
rule  they  do  not  take  much  active  part  in  engineer-
ing the  business  and  controlling  its  general  policy;
and  they  take  no  part  in  superintending  its  details.
