Griffith Observatory’s sundial works as the ancient instruments did. In the morning, when the Sun is in the east, you can see the rod’s shadow on the dial’s west side, which is marked with hour lines. At noon, when the Sun is due south, the shadow is aligned north-south. When the Sun is in the west, the shadow strikes the hour lines on the sundial’s east side. By looking at where the shadow falls on the lines, you can tell what time it is.