Lab
Library
Journal
Shop
Sign in
to keep
1
210
The Fairy-Land of Science
·
Arabella B. Buckley
38
Some
substances
send
back
hardly
any
waves
of
light,
but
let
them
all
pass
through
them,
and
thus
we
cannot
see
them.
A
pane
of
clear
glass,
for
instance,
lets
nearly
all
the
light-waves
pass
through
it,
and
therefore
you
often
cannot
see
that
the
glass
is
there,
because
no
light-messengers
come
back
to
you
from
it.
Thus
people
have
sometimes
walked
up
against
a
glass
door
and
broken
it,
not
seeing
it
was
there.
Those
substances
are
transparent
which,
for
some
reason
unknown
to
us,
allow
the
ether
waves
to
pass
through
them
without
shaking
the
atoms
of
which
the
substance
is
made.
In
clear
glass,
for
example,
all
the
light-
waves
pass
through
without
affecting
the
substance
of
the
glass;
while
in
a
white
wall
the
larger
part
of
the
rays
are
reflected
back
to
your
eye,
and
those
which
pass
into
the
wall,
by
giving
motion
to
its
atoms
lose
their
own
vibrations.
Into
polished
shining
metal
the
waves
hardly
enter
at
all,
but
are
thrown
back
from
the
surface;
and
so
a
steel
knife
or
a
silver
spoon
are
very
bright,
and
are
clearly
seen.
Quicksilver
is
put
at
the
back
of
looking-glasses
because
it
reflects
so
many
waves.
It
not
only
sends
back
those
which
come
from
the
sun,
but
those,
too,
which
come
from
your
face.
So,
when
you
see
yourself
in
a
looking-glass,
the
sun-waves
have
first
played
on
your
face
and
bounded
off
from
it
to
the
looking-glass;
then,
when
they
strike
the
looking-glass,
they
are
thrown
back
again
on
to
the
retina
of
your
eye,
and
you
see
your
own
face
by
means
of
the
very
waves
you
threw
off
from
it
an
instant
before.
Marker
Marker
Fine marker
White-out
Fine white-out
Circle
Paint
Unmarker
Hand
Scalpel
Dice
Sieve
Purify
Undo
Redo
Start over
