Our sundial consists of an engraved ... then shaped this into a hemisphere on a lathe. We attached a small peg to the inner bottom of this mold so there would be a hole for the pin. Next we built a ...

The inventions of the hemispherium and the hemicyclium are attributed to Berosus (356-323 BCE), a Chaldean priest and astronomer who brought these types of sundials to Greece. Both dials use the shape ...