The meridian line
Introduction
Description
The oracle of Apollo
The controversy
Gnomon's lens
Principles
How it works
The problem of penumbra
Animation
The diurnal motion
Solar image
Calculation of the position
Is it noon at midday?
High resolution
Gallery
Gnomon
Meridian line
Cassini room
San Petronio/Perinaldo
Gallery - Cassini room
