For  some  time  after  the  public  opening  of  the
line.  Mr.  Stephenson's  ingenuity  continued  to  be
employed  in  devising  improved  methods  for  securing
the  safety  and  comfort  of  the  travelling  public.  Few
are  aware  of  the  thousand  minute  details  which  have
to  be  arranged  —the  forethought  and  contrivance
that  have  to  be  exercised — to  enable  the  traveller  by
raihvav  to  accomplish  his  journey  in  safety.  After
the  difficulties  of  constructing  a  level  road  over
bogs,  across  valleys,  and  through  deep  cuttings,
have  been  overcome,  the  maintenance  of  the  way
has  to  be  provided  for  with  continuous  care.  Every
rail  with  its  fastenings  must  be  complete,  to  prevent
risk  of  accident ;  and  the  road  must  be  kept  regularly
ballasted  up  to  the  level,  to  diminish  the  jolting  of
vehicles  passing  over  it  at  high  speeds.  Then  the
stations  must  be  protected  by  signals  observable
from  such  a  distance  as  to  enable  the  train  to  be
stopped  in  event  of  an  obstacle,  such  as  a  stopping


272  IMPROVEMENT   OF    ROAD    AND    PLANT      [CHAP  Xll

or  shunting  train  being  in  the  way.  P'orsomc  years
the  signals  employed  on  the  Liverpool  railway  were
entirely  given  by  men  with  flags  of  different  colours
stationed  along  the  line  ;  there  were  no  fixed  signals,
nor  electric  telegraphs  ;  but  the  traffic  was  neverthe-
less worked  quite  as  safely  as  under  the  more
elaborate  and  complicated  system  of  telegraphing
which  has  since  been  established.
