arded either as the dwelling of the numen or as the numen himself,
upon which Romulus is said to have hung the _spolia opima_ taken from
the king of the Caeninenses;[261] here we may see the earliest trace of
the triumphal procession that was to be. Doubtless an _ara_ was here
from the first, and then followed a tiny temple, only fifteen feet wide
as Dionysius describes it from personal knowledge in the time of
Augustus,[262] who restored it. There was no image of the god, but in
the temple was kept a _silex_, probably a stone celt believed to have
been a thunderbolt;[263] this stone the Fetiales took with them on their
official journeys, and used it in the oath, _per Iovem lapidem_, with
which they ratified their treaties. As the Romans thought of Jupiter,
not as a personal deity living in the sky like Zeus, but rather as the
heaven itself, so they could think of him as immanent in this stone,
_Iuppiter lapis_. And the use of the flint in treaty-making suggests
another aspect of the god, which he retained in one way or another
throughout Roman history; it is his sanction that is called in to the
aid of moral and legal obligations, resulting from treaties, oaths, and
contracts such as that of marriage. As Dius Fidius he was invoked in the
common Roman oath _medius fidius_; as Farreus (if this were an old
cult-title) he gave his sanction to the solemn contract entered into in
the ancient form of marriage by _confarreatio_, where his flamen had to
be present, and where in all probability the cake of _far_ was eaten as
a kind of sacrament by the parties to the covenant.[264] In much of this
it is tempting to see, as we can see nowhere else in the Roman religion,
faint traces of a feeling about the heaven-god brought from a remote
pastoral life under the open sky, where neither forest nor mountain
intervened to shelter man from the great Presence;[265] and it is also
tempting to think that there was here, even for Latins who had learnt to
worship Jupiter under the form of stocks and stones in the land of their
final settlement, some chance of the development of a deity "making for
righteousness."

Third and fourth in the order of invocation came Mars and Quirinus, and
the same order held good for their flamines. These two priests may have
been subject to some of the taboos which restricted the Flamen
Dialis;[266] they too, that is, may have been to some extent precious,
and have been endowed in a lost period of history with