Also, D II 6 (the 66th chapter) begins a discussion of "the cause of Rome's subjugation." D III 6 (the 99th chapter) is on conspiracies. D III 39 (the 132nd chapter) is the famous chapter on becoming a "knower of sites." 39 is of course a multiple of 13. This is the ONLY chapter in the book in which 33 and 13 coincide. See the note on Livy's discussion of Alexander, above.