6.1.2 says it takes a merchant vessel not much less than eight days to sail around Sicily. As Dover notes in HCT ad loc. (p.197f.) this is excessive for a journey of roughly five hundred nautical miles, if the vessel sailed continuously with favorable winds. Ephorus (FGr Hist 70 F 135) gave a shorter estimate. Is Thucydides exaggerating or is he simply using a more conservative figure based on a voyage that involved stops for rest or trade, or one that encountered adverse conditions?