"It was the tenth hour by Atticus’s exquisite sundial"

A Modern Sundial
GNU Free Documentation LicenseA Modern Sundial - Credit: SEWilco/Wikimedia Commons
A sundial is a device that allows one to measure the time based on the where the sun’s shadow falls on its surface. The flat surface is usually marked with lines indicating the time of day, with a rod or triangular edge called a gnomon rising from the centre to create a shadow.