Some time after the calendar was drawn up, a deity was established on the Aventine, _i.e._ not within the _pomoerium_, whose arrival marks a development in the organisation of handicraft. We cannot indeed _prove_ that the settlement of Minerva on the Aventine took place so early, but we have strong grounds for the conclusion.[482] This temple was in historical times the religious centre of trade-gilds; and these gilds were by universal Roman tradition ascribed to Numa as founder, which simply means that they were among the oldest institutions of the City-state. As Minerva does not appear in the calendar, had no _flamen_, and therefore must have been altogether outside the original patrician religious system, the natural inference is that the temple was founded, like the shrines of Hercules and the Twin Brethren, towards the end of the period we are dealing with, and was from the first the centre of the gilds. Of those mentioned by Plutarch in his life of Numa (ch. 17), we know that the following gilds belonged to Minerva: _tibicines_, _fabri_ (carpenters?), _fullones_, _sutores_; and it is a reasonable guess that the others, _coriarii_, _fabri aerarii_, and _aurifices_, were also under her protection. These trades, as Waltzing remarks in his great work on Roman gilds,[483] are all in keeping with the rudimentary civilisation of primitive Rome; they are those which were first carried on outside of the family. Workers in iron are not among them; bronze is still the common metal. Now of course we must not go so far as to assume that none of these trades existed before the cult of Minerva came to Rome; but from her close association with them all through Roman history, and from the fact that the Romans were originally an agricultural folk, as the calendar shows, with a simple economy and simple needs, it is legitimate to connect the arrival of the goddess with the growth of town life and the demand for articles once made in rude fashion chiefly on the farms, and with a period of improvement in manufacture, and the use of better materials and better methods. Whence, then, did these improvements come? This is only another way of asking the question, Whence did Minerva come?