As regards the first class of submarines, the present submarine boats engaged in the continental war consist of vessels only a few of which have a surface speed exceeding twelve knots, or a submerged speed exceeding ten knots for one hour or eight knots for three hours. There may be a few in commission that exceed these speeds, but very few. Some are in course of construction that are expected to give a surface speed of seventeen and eighteen knots for forty hours and about eleven knots submerged for one hour, or a slower speed for a greater number of hours. Governments are asking for bids for submarines of greater speed, and some have been designed which are expected to make twenty knots on the surface; but they are not in service as yet. One reason that higher surface speeds have not been reached is the difficulty of securing a perfectly satisfactory high-power, heavy-oil, internal-combustion engine, suitable for submarine boat work. As soon as a proven satisfactory heavy-oil engine is turned out by the engine builders, capable of delivering five thousand horsepower per shaft, submarine boats may be built capable of making up to twenty-five knots on the surface. The submarine, even at its present development, has shown its superiority over the battleship in coast operations; to intercept a battleship at sea, however, even a high-speed submarine must lie in wait, perhaps for days or even weeks at a time, much like a gunner in a "blind" waiting for a flock of ducks to pass within gunshot. Because of its relatively slow speed it would have to wait for a long time, also, for a battleship or fleet to pass sufficiently near to be headed off, especially if the submarine were entirely submerged, because the moment the periscope appears above water the quarry will take to its heels, if it follows the latest ruling of the British Admiralty, to "steer away from the vicinity of submarines at full speed, even if it is necessary to abandon a torpedoed sister ship and its drowning crew to their own fate." I believe that this apparently heartless order is justified by the loss of the _Aboukir_, _Cressy_, and _Hogue_, the only flock of ducks, figuratively speaking, that has come within the shot of the submarine torpedo gunner. The conclusion must be reached, therefore, that on the high seas the only advantage the costly dreadnought has over the pigmy, cheap submarine, as at present constructed, lies in its ability to run away and to rule commerce far offshore on the high seas.