E.C. Marchant, Commentary on Thucydides Book 1

2. αἰεὶ δή ποτε—as δή ποτε means in the past (frequent in tragedy), so αἰεὶ δή ποτε = always in the past, i.e. ‘from the earliest times.’

3. τῶν Ἑλλήνων ... ἐπιμισγόντων—two points are made: (1) the early commerce of the Greeks was carried on mainly by land, (2) the Isthmus was on the high-road between οἱ ἐντός and οἱ ἔξω Π. The sentence would be much clearer with a partic. like πορευομένων, as proposed by Steup, after Ἑλλήνων, so that τε would mean and.

7. ἀφνειόν—we have only one instance, Il. 2.570.

9. μᾶλλον ἔπλῳζον—cf. c. 8. 2.

τὰς ναῦς—the ships referred to in 13.2. These enabled Greece to extinguish piracy, and thus to further her commerce; and the outcome of that, it is implied, was the formation of a considerable fleet.

11. ἀμφότερα with παρέχοντες, in both ways, i.e. as the context shows, by sea and land. ἀμφότερα and κατ᾽ ἀμφότερα do not of themselves mean on both elements, but show the same accus. as τοῦτον τὸν τρόπον, and κατὰ πολλοὺς τρόπους. It is the context that gives the special meaning.

ἔσχον—ingressive.