Since the Lacedæmonians, had they marched direct from the Asopos ridge to this νῆσος, would not have had to traverse a longer stretch of ἱππάσιμος χῶρος than if they had gone round by the ὑπωρέη (vide map), it is difficult to see why they should have adopted the infinitely more circuitous route.
I do not, however, wish to lay too much stress upon this argument, as I believe the real object of the course taken by the Spartans to have been the relief of the convoys blocked up in the pass on the Platæa-Athens road, a reason which may be deduced from Herodotus’ own words in describing the decision to move to the “Island” (ix. 51)—“They determined, on arriving at this place (the ‘Island’), to send off half the army towards Kithæron in the course of this night, to recover the attendants who had gone after the provisions, they being blocked up in Kithæron.”
It does not seem likely that, after the damage which they had suffered in the second position, they could have come to the decision to send off from the νῆσος of Leake and Vischer one half of the army to the pass. It would be obliged to march across a mile of ἱππάσιμος χῶρος between Platæa and Ridge 4, and to venture itself, at a distance of from two and a half to three miles from the remainder of the army.
The reason which mainly influenced both Leake and Vischer in thus determining the site of the νῆσος was no doubt the question of distance from the Asopos. They assumed that when Herodotus used that name he meant the stream coming from Leuktra and the west. It is almost beyond doubt that he does not mean this stream. The Asopos to him was the stream A 1 with the main stream below the junction of A 1; and it is extremely likely that what was the Asopos to him was also the Asopos to the Platæans. It is only necessary to stand on the site of Platæa and look northward over the plain in order to understand how this nomenclature would arise. The course of A 1 is traceable all along the west foot of the Asopos ridge; but the upper course of the main stream is undistinguishable unless the river be in flood.
As this piece of ground fails in such important particulars to harmonize with Herodotus’ account of the “Island,” it remains to be considered whether it is possible to apply his description to any other part of the field.
One fact is quite evident from Herodotus: the “Island” lay between the branches of the Œroë.
I think it is to be found high up in the interval between the branch streams, at the point indicated in the map, and that it consisted of Ridge 4, and possibly of Ridge 3 also. Any one who takes the higher track from Kriekouki to Kokla cannot fail to be struck by the peculiarity of the ground, should he happen to look down towards the plain at the point where the road passes close to the narrow strip of land which separates the sources of the streams O 1 and O 3. These sources, as will be seen from the map, are close together, and the ridge which separates them is quite low at the narrowest part. The stream O 3 (east branch) flows down towards the plain at first in a deep valley with a very steep slope towards the “Island,” which valley it leaves at the point where the streams which unite to form O 3 have their junction. From this point it flows beneath the “Island,” which rises steeply above it, whereas on the other side of the stream, i.e. on the west side, the ground slopes quite gradually up to the rounded back of the low-lying Ridge 5.
The stream O 1 flows down to the plain in a deep depression.
It is true that at the present day these streams do not join immediately on reaching the plain; but to show how possible it is that their courses in the flat alluvial ground may have altered again and again, within certain limits, in the course of time, I may mention that when Colonel Leake visited this ground, the stream O 2 did not join O 3 at the point where it now joins it, but was a separate stream from it at the point where the Kokla-Thebes track passes the branches of the Œroë, i.e. more than a mile below their present junction.
There is another very striking point about this piece of ground, which is noticeable in its contouring in the map. Its insular character is, if I may so say, emphasized by a large hillock which rises on it close to O 3, and which is a most prominent object, especially when viewed from Platæa itself. This hillock may be identified by any one visiting the ground, owing to its having on the south slope of it a white building, the only building existing between Kriekouki and Kokla.