The problem of the naval architect henceforth was greatly simplified. Masts and sails, which had in the past proved such an embarrassment, were now frankly abandoned, with the result that a thousand difficulties which had beset the designer of the turret ship were swept away. No longer had the stability curve to conform to the conflicting requirements of the sailing vessel and the gun platform. The large weight gained by dispensing with masts and sails could be embodied as an addition to the armament or to the fuel carried. The single screw, which in the case of a ship intended to use sails had been almost a necessity, could be replaced by twin screws of greater power; and the change would remove the liability of complete disablement, and give a number of constructive advantages which it is unnecessary to enumerate. Indeed, it may be said conversely, that the adoption of twin screws so improved the reliability of the propelling machinery as to make practicable the abandonment of masts and sails. In April, 1869, the _Devastation_ was commenced. Designed by Sir Edward Reed, she “forestalled, rather than profited by, the dreadful lesson of the _Captain_ and by her success gave proof of the judgment and initiative of the Board and their adviser.” Sir Edward Reed had recognized, more fully than his critics, the conflicting elements inherent in the rigged turret ship. And it is significant that, just at a time when the assured success of the _Monarch_ must have been a gratification to her designer, he should record: “My clear and strong conviction at the moment of writing these lines [March 31st, 1869] is that no satisfactorily designed turret ship with rigging has yet been built, or even laid down.” The _Devastation_ design was a development of those of some previous mastless turret ships, the _Cerberus_, the _Hotspur_, and the _Glatton_ class, which had embodied Sir Edward Reed’s ideas as to the requirements of coast-service vessels. At first given four 25-ton guns, the _Devastation_ was ultimately armed with four M.L. guns each weighing 35 tons and carried in turrets on the centre-line, one at each end of a central breastwork, 150 feet in length, built round the funnels. This central breastwork, raised above the upper deck and armoured along its sides with 10-inch steel, supported the two turrets and enabled the guns to be carried at a desirable height above the water-line. The upper deck itself was low. The sides, up to its level, were protected by a complete belt of armour 8 inches in thickness. The abolition of masts and rigging had a striking effect on the design. Compared with the _Monarch_, of nearly the same tonnage, she carried heavier guns, double the weight of armour, double the amount of fuel, and required little more than half the crew to work her.