the protected guns can be ranged along the length of the broadside instead of being concentrated in a central battery. There are, however, the accompanying disadvantages of having bow and stern heavily burdened, and of the resulting increase in the total weight of armour. For wood-built iron-clads this plan has the additional advantage of protecting the upper works throughout the length from the destructive effects of shells. The French ships are, for the most part plated in this manner". "In 1861 many verbal discussions took place between myself [the Controller] and the constructors of the day, as to the cause of the excessive rolling of our ships, when compared with similar French constructions. When I [the Controller] urged upon them the possibility of adding largely to the armour plating of the ships, and of not confining it, as had been done, in the Warrior and other ships, I was met with very great opposition, and my endeavours to get the five wooden ships wholly Armour-Plated were met by two reasons against doing so. One was, that extensive armour-plating must cause excessive rolling; and the other, that there were doubts of the stability of a ship wholly armour-plated. Now it turned out that the stability of these ships wholly armour-plated proved excessive, and, if their stability had been lessened, their rolling would have been diminished; but the Constructors of the Navy were not alone in their opinion." "In the wood ships the [4.5 inch thick] armour was bolted on outside the planking of an ordinary line-of-battle ship, being consequently backed by about 30 inches of timbering and planking." This compared with armour backed by of teak for the , , Achilles and the , and armour backed by of teak for the Minotaur class. Rolling In the 1860s rolling was measured as the sum of the angles to port and to starboard. "Admiral Dacres Report for 1864 [on the Channel Squadron] shows that on the four days when all the ships were together, the means of the extreme rolls recorded were as follow: Hector, 10 degrees; Warrior and Defence, 10.25; Black Prince, 11.05; Prince Consort, 11.75; and Edgar (wooden line-of-battle ship), 14.25. The Warriors rolling was measured by a different instrument from that used on board the other ships, so that she cannot fairly be compared with them. This record is, however, of great interest, on account of the comparison it