Book 1 1.1-1.20 1.21-1.25 Book 2 2.1-2.20 2.21-2.40 2.41-2.54 Book 3 3.prooemium-3.19 3.20-3.31 Book 4 4.1-4.20 4.21-4.40 4.41-4.60 4.61-4.80 4.81-4.83 Book 5 5.1-5.20 5.21-5.40 5.41-5.60 5.61-5.72 Book 6 6.1-6.20 6.21-6.40 6.41-6.60 Book 7 7.prooemium-7.19 7.20-7.39 7.40-7.59 7.60-7.79 7.80-7.81