Clear and definite as the incidents are which lead Darius to the Danube, the river is no sooner crossed than everything passes into northern mists, into the marvellous and the incredible. Let us first consider the conduct of the Scoloti. The kings of the barbarous north, though far distant from each other--Herodotus gives the land of the Scoloti a length and breath of 500 miles--meet in a great congress. Where the congress was held we are not told. The kings of the Agathyrsi, Neuri, Melanchlæni, and Cannibals find that the matter does not concern them, for they had not invaded Media. But the distant tribes to the east beyond the Don, the Sarmatians, Budini, and Geloni, come a distance of hundreds of miles to assist their neighbours; they carry their public spirit so far as to sacrifice their own lands, regardless of which the Budini and Geloni march with Idanthyrsus first to the north and then to the west; the Sarmatians follow Scopasis far to the north-east. Why the Scythians divided their army in the first instance, why they did not unite to meet Darius, we cannot ascertain. We are not told what Idanthyrsus is doing while Scopasis retires to the Volga; we only know that the two armies again unite, while Darius is building the castles on the Volga. When united the Scythians retire to the west as far as the borders of the Agathyrsi, _i.e._ to Transylvania, the most foolish thing for their own interests which they could have done, for by this means they brought Darius back into the neighbourhood of the Danube. On the borders of the Agathyrsi Darius summons them to battle. The princes answer that they will fight if he attacks the tombs of their fathers. These tombs we have found in the neighbourhood of the Gerrhus; they are the numerous Kurgans below the rapids of the Dnieper,[269] a region which Darius must have traversed on his way north-eastwards to the Volga. Darius does not accede to the request of the Scythians. Nevertheless they determined to attack the Persians, and yet contradict the object of this attack by sending Scopasis with his army and the Sarmatians to the Danube, thus weakening the army. When Scopasis and the Sarmatians are gone, Idanthyrsus offers the battle hitherto so carefully avoided, with cavalry and infantry, though Herodotus remarks that the Scythians have no infantry. Meanwhile Scopasis comes with his army to the Danube, not to fight with the Greeks but to treat with them. What reasons had the Scythians not to treat the Greeks as enemies? If they wished to cut off the return of Darius, they must attack the bridge and destroy it. If they thought that they could not do this, or did not wish to do it, but to treat, they need not have sent half the army with the Sarmatians, but only a few horsemen. The Greeks were able to protect the bridge with a fort, upon which the Scythian cavalry could hardly have made any effectual impression, or if they neglected to do that, they