All  our  life  illusions  brood  over  us.  The  night
is  only  a  shadow  —  the  negation  of  hght;  and
yet  it  plays  a  part  in  our  lives  as  real  as  that  of
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HORIZON  LINES

health  or  friends  or  climate,  as  real,  but  of  another
kind.
Time  itself  is  an  illusion.  The  future  does  not
exist  nor  the  past;  yet  how  are  our  lives  influenced
by  the  memory  of  the  one  and  our  anticipations  of
the  other!

The  world  is,  indeed,  full  of  illusion.  We  fancy
that  luminous  bodies  shoot  out  rays  of  light  such  as
we  appear  to  see  when  we  look  at  them.  We  see
beams  and  scintillations  when  we  look  at  the  stars
and  the  sun;  but  is  it  not  all  a  trick  of  the  eye?  The
light  from  a  luminous  body  goes  out  in  all  directions,
not  in  separated  rays,  but  as  vibrations  in  the  ether.
When  we  throw  a  stone  into  a  still  pool  of  water  a
wave  motion  is  set  up  which  spreads  in  concentric
circles.  But  the  vibrations  called  "light,"  considered
as  a  whole,  assume  the  form  of  a  sphere;  they  go
from  the  luminous  body  to  every  point  of  a  hollow
sphere.  We  see  a  star  as  a  bright  point  in  the  sky,
but  if  the  universe  were  full  of  eyes,  every  eye  could
see  that  star;  its  light  goes  to  every  point  of  the  hol-
low sphere  of  Infinity.  But  no  more  than  does  the
light  of  the  candle  in  your  hand,  or  the  lamp  on
your  table  go  to  Infinity,  if  unobstructed.  Stars
which  cannot  be  seen  by  the  most  powerful  tele-
scope must  yet  radiate  their  light  into  infinite  space.
