According to professor tilson's lecture on rome, the layered squares seen in panini's painting of the interior of the pantheon are called which, beyond creating depth and visual interest to the curvature of the dome, significantly reduce the overall weight of the buildin

Coffers are the layered squares seen in Panini's painting of the interior of the pantheon. Coffers, while beyond creating depth and visual interest to the curvature of the dome, significantly reduces the overall weight of the building based on the lecture on Rome by Professor Tilson.

The coffers usual purpose is being used as ornamentals in ceilings.

the answer to your question is,

d. when a child was born.

-mabel < 3