This was the infancy period of the iron-clad ship. The race between guns and armor was barely begun, and manufacturing processes still were crude. As these improved, with astounding rapidity, the successful production of rifled cannon of ever-increasing dimensions and penetrative force imposed an increased armor protection, which at the first was obtained chiefly by an increase of thickness, _i.e._, of weight. As guns and armor got heavier, ships had to be bigger to carry them, and, if bigger, of course longer. But the monitor idea, admirably suited to small ships, had now fast hold of men’s minds—in England especially, for the United States lapsed into naval somnolence after the war—and it was carried irreflectively into vessels of huge dimensions whose hulls rose much above the water. Weight for weight, the power of the gun outstripped the resistance of armor, and it soon became evident that even in a large ship perfect protection could be given only to a part of the structure. Passing over intermediate steps, the extreme and final development of the monitor idea was reached in the _Inflexible_, planned in 1876 by the British Admiralty, built in the following years, and still in service. This vessel was of eleven thousand eight hundred and eighty tons displacement. She was three hundred and twenty feet long, and of that length only the central one hundred and ten feet had protection, but that was by armor two feet thick, while armored partitions extended from each end of this side belt across the vessel, forming a box one hundred and ten feet long by seventy-four broad. Within this box were two turrets, each with sixteen inches of armor, and carrying two guns which threw a shell of a ton weight. THE COMING OF THE MONITOR