this  equitable  proceeding  will  be  considered  briefly
in  this  place.]
Generally  an  ac-       In  general,  it  was  necessarv,  in  order  to  maintain

tion  must  already  o  '  ^  '

!if/noed^"  """^  ^  ^^'^  °^  discovery,  that  an  action  should  have  been
already  commenced  in  another  court,  to  which  the
discovery  would  be  auxiliary.  There  were,  how-
ever, exceptions  to  this  rule,  as  where  the  object  of
the  discovery  was  to  ascertain  who  was  the  proper
-  party  against  whom  the  suit  or  action  should  be
brought.     But  these  cases  were  of  rare  occurrence.^

Jurisdiction  in         The  power  of  the  courts  of  equity  to  compel  dis-

equity  arose  ,  •       it       i-  i  •■i-i-i-

oeoaust  at  law     covery  arose  principally  from  the  original  inability

defendant  could  •'  c-  tr      j  o  J

not  be  examined  of  courts  of  Common  law  to  compel  a  complete  dis-

on  oath,  or  lie  l-  r

p?od^Ql!e''do*cu-     covery  of  the  material  facts  in  controversy   by  the
™''"*^-  oaths  of  the  parties  to  the  suit,  and  also  from  their

original  want  of  power  to  compel  the  production  of
deeds,  documents,  writings,  and  other  things  which
were  in  the  custody  or  power  of  one  of  the  parties,
and  were  material  to  the  right,  title,  or  defence  of
the  other.  Bills  of  discovery  were  greatly  favored
in  equity,  inasmuch  as  they  tended  to  assist  and
promote  the  administration  of  justice  in  others,  and
they  would  be  sustained  in  all  cases  where  some  well-
founded  objection  did  not  exist  against  the  exercise
of  the  jurisdiction.
Defences  to  a  bill  The  principal  grounds  upon  which  a  bill  of  discov-
ery  might  have  been  resisted  were  as  follows: — 1.
