Brenton's essay in what 1850?
The Qumran caves were found in the 1940s! They are still yeailding new documents including COPIES OF THE SEPTUAGINT.
Nothing uncovered in the DSS can change the facts of history regarding Origen's Hexapla, and nothing uncovered in the DSS challenges Brenton's Essay on the Septuagint, which is a fair presentation of facts on the matter.
BTW when you use the word "Septuagint", what arre you referring to: the Greek translation of the OT that supposedly took place under the auspices of the Jewish authorities or any Greek translation of the OT regardless of who did it and when --- and just how do you know the difference???
And just how come Origen's Hexapla had one column for the Hebrew but five for the Greek and he had to use Theodotian's in the sixth column to create his fifth column which became the OT of Codex B. If the Septuagint was so authoritative and standardized in Origen's day, why was it not in the first column instead of the Hebrew text???