Lapis manalis

The other was used to make rain; this one may have no direct relationship with the Manes, but is instead derived from the verb manare, "to flow".

Most cities of Latium and Etruria contained a similar pit or ditch; Plutarch describes the custom of a mundus as being of Etruscan origin, and states that it was used as a place where first-fruits were deposited.

[4] This stone was ceremonially opened three times a year, during which spirits of the blessed dead (the Manes) were able to commune with the living.

[8] During the ceremony, the pontifices had the stone brought from its usual resting place, the Temple of Mars in Clivo near the Porta Capena, into the Senate.

Offerings were made to Jupiter petitioning for rain, and water was ceremonially poured over the stone.