Spherical sundials, such as the one erected in 2006
in the vicinity of the Max Valier Observatory in
Italy [12], are essentially globes which simulate
the Earth’s orientation in space. On this particular
globe there are 24 metal pins along the equator at
each 15◦ longitude, and a pin at the intersection
point of the local meridian with the equator. The
shadows of the pins show whether the sun is north
or south of the equator. At the equinoxes, the
shadows of all pins fall along the equator. With
the help of the shadows of the pins (figure 7)
one can approximately determine the local solar
time.