Job xxxvii. 16:  “Dost thou know the balancings of the clouds?”  In the Septuagint διάκρισιν νεφῶν may mean “the separate path of the clouds” (Vulg. “semitas nubium,”) or “the dissolving,” as in Aristotle (Meteorol. I. vii. 10:  διακρίνεσθαι καὶ διαλύεσθαι τὸ διάτμίζον ὑγρὸν ὑπὸ τοῦ πλήθους τῆς θερμῆς ἀναθυμιάσεως, ὥστε μὴ συνίστασθαι ῥαδίως εἰς ὕδωρ.  “The moist vapour is separated and dissolved by the great heat of the evaporation, so that it does not easily condense into water.”  Cf. Plato, Sophistes 243 B:  διακρίσεις καὶ συγκρίσεις.