E.C. Marchant, Commentary on Thucydides: Book 3

τὸ οὖν μεταξὺ τοῦτο—‘this intervening space was oceupied with buildings assigned as quarters to the sentries.’ So Stahl, who views τὸ μεταξύ as subjeet, and οἰκήματα as internal accus., as in τὸ ἐναντίον ὄνομα μετωνόμασται I. 122. Steup agrees with this rendering, but he is inelined to retain οἱ ἑκκαίδεκα πόδες and he regards οἰκήματα as pred. nom. Another view, which is to be rejected, is that τὸ μεταξὺ τοῦτο is adverbial accus., ‘in this space,’ and οἰκήματα subject of ᾠκοδόμητο: the constr. is then very strained, and the perf. partic. διανενεμημένα unnatural, implying that the quarters were distributed before they were built.

ἦν ξυνεχῆ—I agree with Steup in rendering ‘it was (all) continuous,’ without any definite subject, as in I. 8 πλωιμώτερα ἐγένετο, and cf. II. 3 ἁμάξας . . ἐς τοὺς ὁδοὺς καθίστασαν, ἵν᾽ ἀντὶ τείχους ᾖ, for it was not only the guards' quarters, but the two parallel walls as well that ‘looked like one thick wall.’