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 character of the cult in Latium was secondary, and that the connection of the temple and cult with the Roman cavalry was a natural result, but not a primary feature, of its introduction. I should be inclined to look on it as coming in with the building of the temple, which was probably of later origin than the original introduction of the cult.