The Battle of Tsushima resulted in the “all-big-gun one-calibre battleship of high speed.” How this came about has been admirably demonstrated by Lieut.-Commander Simms, of the United States Navy, and chief of the American naval artillery department, in a remarkable report on the battle and its influence on shipbuilding. “Experiments have shown,” he wrote, “that it is exceedingly difficult to hit an enemy at long range when the range is changing rapidly. This is, of course, not true at short range, but at long ranges half the danger spaces--those at which the gun sights must be set in order to hit--are so small, say 50 yards. The bearing of these facts on naval tactics is very important, since it means that, generally speaking, you cannot make many hits at long range while you are manœuvring. Conversely, you will not receive many hits at such a time, because, when at short ranges, the most dangerous position in which a ship can place itself is end-on to the enemy. It is usually assumed that this is equally true at all ranges; but this is not the case, provided the rate of change in fire is rapid.... From the point of view of the theory of gun-fire alone it would be unwise to think of building a man-of-war of any type having more than one calibre of gun in her main battery. In other words, it may be said that the abandonment of the mixed battery ships in favour of the all-big-gun one-calibre ship was directly caused by the recognition of certain fundamental principles of naval marksmanship developed by gunnery officers.” [Illustration: U.S. SCOUT “SALEM.” _Photograph supplied by the Fore River Shipbuilding Co._] [Illustration: U.S. CRUISER “MAINE.” _Photograph supplied by the W. Cramp & Sons, Ship and Engine Building Co., Philadelphia._]