1.41

τὸ μὲν οὖν πρῶτον: "now at first."  μὲν οὖν is used here (and also again in the beginning of the next sentence) to effect a transition as often in prose (Denniston GP 470-472). Given the relative paucity of particles in English, it is difficult to render this transitional function with a clear English equivalent.  For the adverbial τὸ πρῶτον, see S. 1611. 

ἑωρῶμεν: impf. of ὁράω, "we saw."

ἐφάνησαν: aor. pass. 3 pl. of φαίνομαι, "appeared."

ὅσον ἑξακόσιοι: "about 600" (for ὅσον as "about, approximately," see LSJ IV.3).

διαστάντες: aor. part. of διίστημι, "standing apart."

πολλαὶ (sc. νῆσοι)...ἀντίπρῳροι: "many islands prow to prow" (i.e. facing one another). In describing the mobile islands as boats, Lucian uses "prow" throughout this passage to describe the front-facing part of each island.

συνηράσσοντο: impf. of συναράσσω, "dashed together."

ἐμβληθεῖσαι: aor. part. pass. of ἐμβάλλω, "having been rammed." Jerram notes that this type of attack against the side of a ship was called ἐμβολή (as opposed to προσβολή which involved a frontal confrontation from one ship's prow to the other).

διηγωνίζοντο: impf. mid. of διαγωνίζομαι, "battled each other."

οἱ γὰρ ἐπὶ τῆς πρῴρας τεταγμένοι: perf. part. mid-pass. of τάσσω, "those stationed at the prow."

πᾶσαν ἐπεδείκνυντο προθυμίαν ἐπιβαίνοντες καὶ ἀναιροῦντες: "showed the utmost zeal in boarding and killing."

ἐζώγρει δὲ οὐδείς: "and no one took any captives" (i.e. they killed one another and didn't keep any hostages).

ἀντὶ χειρῶν σιδηρῶν: "instead of iron hands" (i.e. grappling hooks).

πολύποδας μεγάλους: "giant octopuses." Jerram refers the reader to Aelian's Varia Historia for more on the habits of the polypus.

ἐκδεδεμένους: perf. part. mid.-pass. of ἐκδέω, "fastened (sc. with lines)."

ἔβαλλον...καὶ ἐτίτρωσκον (sc. ἀλλήλους): "they struck and wounded (sc. each other)."

ὀστρέοις τε ἁμαξοπληθέσι: "with oysters that would fill a wagon."