Refraction and fishermen
As the light from the fish leaves the water it bends away from the
normal (right angled line to the surface). This makes the fish appear to be nearer to the
surface.
If the fisherman aims at the centre of the fish the spear will miss (the spear
passing in front of the fish) but if they aim at where they think the tail is then they will hit the
body of the fish.
