Six boilers supplied a single compound engine for a theoretical top speed of 13.5 knots. The ships also carried a 9-inch Armstrong gun that crews could reposition by cable to fire through forward ports and along selected arcs. A wrought-iron armour belt provided respectable protection for its period, though it was no longer exceptional by later standards. These features were the technical starting point for the Imperial Arsenal reconstruction.
Chapter · 6:36-7:44
Original machinery, armour, and movable chase gun
The class's original configuration combined compound steam machinery, a wrought-iron belt, and a 9-inch Armstrong gun that could be shifted to fire along forward arcs.