In the thrice famous days of Nelson, it was still our "wooden walls" which carried the flag of England on from triumph to triumph. At the battle of Trafalgar the _Victory_ and the French ship the _Redoubtable_ were brought up close alongside of each other, and in this position poured volley after volley upon each other's bulwarks, until water had to be thrown over the ships' sides to prevent them igniting. The _Victory_ was a grand ship in her time, yet she was not more than two thousand tons burden, and her guns were but one hundred and two in number. But at last the day arrived when it became manifest that the glory of our "wooden walls" had set. In the prime of his intellectual and physical strength, the Emperor Louis Napoleon was a man of active and subtle brain, and it was to his ingenious invention that the first ironclad ship of war owed its birth. Floating batteries protected with iron plates were first employed during the Crimean War. It was becoming manifest that the great strides which were being made in the manufacture of cannon must necessitate an improved system of defensive armour for ships of war. No wooden vessel that could be constructed could be proof against the new guns that were now coming rapidly into use. The French, as has been just indicated, were the first in the field with the new style of war-ships. _La Gloire_ was built, and was quickly followed by our own _Warrior_. The frame of _La Gloire_ was constructed of wood, but covered with an iron plating four and a half inches in thickness. The _Warrior_ was built on an iron frame, and her armour-plating is of the same thickness as that of _La Gloire_; the lining is of solid teak eighteen inches thick, which is again backed by an inner coating of iron. The length of the _Warrior_ is three hundred and eighty feet, but only about two-thirds of this is iron-plated. At this time--the early days of ironclads--the heaviest shot that could be thrown by any gun was a sixty-eight pounder. Guns of this calibre the _Warrior_ and her class were proof against. But the guns increased rapidly in size and power, and the thickness of the armour with which the ships were protected had to be increased in proportion. The class of war-vessels which succeeded the _Warrior_ were entirely cased with iron plates, whose thickness has from time to time been increased. Since the first ironclad was built, then, a contest--for only such it can be called--has been going on between the cannon-maker and the ship-builder, the one striving to construct a gun which shall pierce the thickest armour which the ship can carry, the other adding inch upon inch to his armour plates, to the end that they may be shot-proof; and this contest may be said to be going on at this hour.