87 x 2 x1 x 20 feet timber longitudinals, common braced timber trestles (piers 12 through to 100) or common concrete piers (piers 23–26, 31–32, 34, 38, 41, 51, 53, 58, 61, 64, 66–68, 71–72, 74, 76–80, 82–83, 85, 96-98).