Time is read from an equiangular scale around
the equator. Noon (12 h) is indicated at the point
of intersection of the equator and the meridian of
the dial’s location. The shadow of a pin at this
location is shortest at noon. The current solar time
at the place of the sundial is read by looking for the
pin with shortest shadow and its angular separation
from the sundial’s meridian. A spherical sundial
with pins is an improved version of Jefferson’s
spherical sundial, which uses a movable vane to
read the time [13].