"The usual form of independent monumental tombs was a ponderous tower-shaped block, sometimes square, and sometimes round, with a quadrangular substructure; as, for instance, the tomb of Cæcilia Metella at Rome, which belongs to the time of Julius Cæsar, and which was used in the Middle Ages as a fortress, with battlements added to it.

Tomb of Cæcilia Metella

"The usual form of independent monumental tombs was a ponderous tower-shaped block, sometimes square,…