The attitude of Argos was also calculated to cause alarm. It must be pointed out at the same time, that though it aggravated the situation to a certain extent, it did not affect it so decisively as has been imagined by modern commentators. The possibility of the landing of Persian troops behind the defences of the Isthmus was not a question so much dependent on the action of Argos as on the success or failure of the Greek fleet in checking the advance of the enemy’s ships before they succeeded in crossing the Saronic Gulf. Had the Persian fleet once succeeded in establishing itself in some harbour of the coast of Argolis, the defence of the Isthmus must have collapsed, whatever the attitude of Argos might have been. This State, owing to the losses it had suffered in the great defeat which Kleomenes and the Spartans inflicted upon it, can hardly have been in a position to offer serious resistance to a landing on its coasts. Note.—The relation of date between the return of the embassies and the retreat from Tempe is of considerable importance to a right appreciation of the situation at this critical time. Herodotus dates the events in Greece by the advance of Xerxes’ army. Thus the expedition to Tempe is stated to have taken place βασιλέος τε μέλλοντος διαβαίνειν ἐς τῆν Εὐρώπην ἐκ τὴς Ἀσίης, καὶ εὄντος ἤδη ἐν Ἀβύδῳ. H. vii. 174. Again, the embassies seem to have been despatched simultaneously to Sicily, Corcyra, Crete and Argos (H. vii. 148, 153, etc.). That to Sicily would almost certainly be the last to return. Gelo did not send the treasure-ships to Delphi until after the visit of the embassy (H. vii. 163, _ad init._), and he did not send them till _after_ he had heard that Xerxes had crossed the Hellespont. If, then, the rough chronology of Herodotus can be relied upon,—and there is not any other source of information upon the subject available,—the Greeks who assembled at the Isthmus after the withdrawal from Tempe must have known that the resources then at their disposal were all upon which they could reckon in the coming struggle. _Note on the Carthaginian Invasion of Sicily._ The satisfactorily attested fact that a large Carthaginian Army attacked Sicily simultaneously with the invasion of Greece by Xerxes raises the very difficult question whether the coincidence in time between the two attacks was anything more than accidental; and, if it was, as to the exact nature of the relation between them. Before discussing the question, it may be well to collect together the various passages in ancient authors in which reference is made to the nature of the Carthaginian campaign. H. vii. 165.