With the burnt-sacrifice and the joyous banquet in our minds we turn to the supposed festival of Zeus at Athens and mark the contrast, a contrast it will be seen so great that it compels us to suppose that the ritual of the festival of the Diasia had primarily nothing whatever to do with the worship of Olympian Zeus. THE DIASIA. Our investigation begins with a festival which at first sight seems of all others for our purpose most unpromising, the Diasia[25]. Pollux, in his chapter[26] on ‘Festivals which take their names from the divinities worshipped,’ cites the Diasia as an instance—‘the Mouseia are from the Muses, the Hermaia from Hermes, the Diasia and Pandia from Zeus (Διός), the Panathenaia from Athene.’ What could be clearer? It is true that the modern philologist observes what naturally escaped the attention of Pollux, i.e. that the _i_ in Diasia is long, that in Διός short, but what is the quantity of a vowel as against the accredited worship of an Olympian? To the question of derivation it will be necessary to return later, the nature of the cult must first be examined. Again at the outset facts seem against us. It must frankly be owned that as early as the middle of the seventh century B.C. in common as well as professional parlance, the Diasia was a festival of Zeus, of Zeus with the title Meilichios. Our first notice of the Diasia comes to us in a bit of religious history as amusing as it is instructive, the story of the unworthy trick played by the Delphic oracle on Cylon. Thucydides[27] tells how Cylon took counsel of the oracle how he might seize the Acropolis, and the priestess made answer that he should attempt it ‘on the greatest festival of Zeus.’ Cylon never doubted that ‘the greatest festival of Zeus’ was the Olympian festival, and having been (B.C. 640) an Olympian victor himself, he felt that there was about the oracle ‘a certain appropriateness.’ But in fine oracular fashion the god had laid a trap for the unwary egotist, intending all the while not the Olympian festival but the Attic Diasia, ‘for,’ Thucydides explains, ‘the Athenians too have what is called the Diasia, the greatest festival of Zeus, of Zeus Meilichios.’ The passage is of paramount importance because it shows clearly that the obscurity lay in the intentional omission by the priestess of the cultus epithet Meilichios, and in that epithet as will be presently seen lies the whole significance of the cult. Had Zeus _Meilichios_ been named no normal Athenian would have blundered.