Laudator Temporis Acti

Diodorus Siculus 19.17.6-7 (tr. Robin Waterfield):

[6] Some Persians lived thirty days' journey away, but even they received their orders on the very day they were sent out, because of their ingenious system of lookouts, which deserves a mention. [7] Persis is corrugated with many valleys, and there are a great many lofty observation points, one after another, on which the men with the loudest voices are posted. Since the places are separated by the distance a human voice can carry, those who received the order passed it on in the same way to others, who did the same again, until the message reached the limits of the satrapy.

[6] ἀπέχοντες δ' ἔνιοι τῶν Περσῶν ὁδὸν ἡμερῶν τριάκοντα τὸ παραγγελθὲν αὐθημερὸν ἤκουον διὰ τὸ φιλοτεχνηθὲν περὶ τὰς φυλακάς· ὅπερ οὐ καλῶς ἔχει παραδραμεῖν. [7] τῆς γὰρ Περσίδος οὔσης αὐλωνοειδοῦς καὶ σκοπὰς ἐχούσης ὑψηλὰς καὶ πυκνὰς ἐπὶ τούτων ἐφειστήκεισαν οἱ μέγιστον φθεγγόμενοι τῶν ἐγχωρίων· διῃρημένων γὰρ τῶν τόπων εἰς φωνῆς ἀκοὴν οἱ παραλαμβάνοντες τὸ παραγγελθὲν ὁμοίως ἑτέροις παρεδίδοσαν, εἶτ' ἐκεῖνοι πάλιν ἄλλοις, ἕως εἰς τὸ τέρμα τῆς σατραπείας τὸ δοθὲν παραδοθῇ.