in touch with the Mediterranean business of
that day. There he was destined to remain, with all the honour of an
oldest cult, though other cults of the same god came in later, and were
established quite close to him; and though never a State deity of much
importance, he exercised a wholesome influence in matters of trade, as
the god who sanctioned your oath, and who accepted the tithe of your
gain which you had vowed at the outset of an enterprise.[477]

In the same period, though the traditional date of their temple is
later, came the Twin Brethren, Castor and Pollux, and found their way,
like Hercules, into the city within the _pomoerium_. The famous temple
of Castor (before whom his brother gradually gave way) was at the end
of the Forum under the Palatine, close to the fountain of Juturna, where
the Twins watered their horses after the battle of Lake Regillus; and
there the beautiful remains of the latest reconstruction of it still
stand.[478] This position alone should make us feel confident that the
cult did not come direct from Greek sources; and it had its origin,
perhaps, in the period when Rome was in close relation with Latin
cities, which themselves had been gradually absorbing the cults and
products of the Greeks of Campania. There is a strong probability that
it came from Tusculum, with which the legend of the Regillus battle is
closely connected, and where the cult had beyond doubt taken strong
root.[479] Like the Hercules of the _ara maxima_, the Twins were no
doubt brought by the course of trade, which was continually pushing up
from the south; for they too were favourites of the merchant adventurer,
and throughout Hellas were the special protectors of the seafarer. Their
connection with horses is well known, and not as yet satisfactorily
explained in its Roman aspect; but Dr. J. B. Carter thinks that they
first became prominent in Greece when the Homeric use of chariots was
abandoned for a primitive kind of cavalry, and that "the Castor-cult
moved steadily northward (from Magna Graecia), carried, as it were, on
horseback," and that when it reached Rome it became connected with the
reorganisation of the cavalry. This seems to be almost pure guess-work,
and, attractive as it is, I fear we cannot put much faith in it.[480]
The position in the Forum, and the well-known connection of both twins
with oaths,[481] seem to me rather to suggest a more natural origin in
trade. I would suggest that the equine chara