ἥκοντες—came in due course. Note that ἥκω has the meaning (1) to appear duly—in court, of litigants, (2) to return from an errand, (3) to reach one's destination.
ὅσα τε ἀπὸ—the oral message. ἀπὸ describes the means. Cf. Aristoph. Eq. 539 ἀπὸ κραμβοτάτου στόματος μάττων ἐπινοίας; Vesp. 656 λογίσαι μὴ ψήφοις, ἀλλ᾽ ἀπὸ χειρός.
ἐπηρώτα—why is the indic. used here? Probably because Thuc. refers only to one occasion, though many asked questions on that occasion.
ὁ γραμματεὺς—sc. τοῦ δήμου. Cf. Arist. Ath. Pol. c. 54 χειροτονεῖ δὲ καὶ ὁ δῆμος γραμματέα τὸν ἀναγνωσόμενον αὐτῷ καὶ τῆ̣ βουλῇ, καὶ οὗτος οὐδενός ἐστι κύριος ἀλλὰ τοῦ ἀναγνῶναι.
τοῖς Ἀθηναἰοις—i.e. in the ecclesia. Probably, if we may infer from the decision arrived at, a special summons (κατάκλησις) had been issued to the country population, among which Nicias found his chief support.
δηλοῦσαν—regular word with ἐπιστολή, ψήφισμα, νόμος, στήλη.
τοιάδε—the letter is in the form of a set speech. (It is entitled in F (Augustanus) πρὸς τοὺς ἐν Ἀθήναις Νικίου ἐπιστολή. Cf. T. Its full description would run, according to the rules of Hermogenes, which are followed throughout the rbetorical scholia of Thuc., ἠ στἀσις πραγματικἠ, λογική (or ἄγραφος), συμβουλευτικοῦ εἴδους, κεφάλαιον ἔχουσα τὸ συμφέρον. Cf. the third letter of Isocrates, written after Chaeronea to Philip.)
