So far as we are aware the only nation that has seriously taken up the question of an antidote to submarines is Great Britain. At present the submarine boat, owing to its slow speed and narrow radius of action, is more suited for defence than attack, though as it is year by year improving it may soon become a valuable attacking weapon. France has preferred to build torpedo-boats and Great Britain destroyers, and on January 15, 1901, France had 235 torpedo-boats and 9 destroyers, and Great Britain had 95 torpedo-boats and 89 destroyers, and in the same way while France is rapidly constructing a flotilla of submarines, Great Britain, although building a few submarines, is also devoting attention to the best method of meeting under-water attack. The means of attack against submarines at present are:— 1. By quick-firing guns. 2. By firing shells full of high explosive, which bursting in the water near the boat, will beat it in. 3. By firing explosives at the end of a spar. When running awash, the submarine presents a very small target; the hull is 3 to 5 feet below the surface, which would deflect all projectiles from machine guns, and the armoured conning tower, which is alone visible, would be a difficult object to hit. After running awash for some distance the submarine will submerge herself, but in spite of periscope and optical tube she will most probably have to come to the surface once or twice to take a short sharp look round before firing her torpedo. This is the moment when the attack must be made upon the diving vessel, and the idea is to destroy her either by firing a shell from a gun, or an outrigger torpedo from a swiftly moving vessel. In so much as it is difficult to make a shell burst with certainty at the right instant, the second method is the one that seems most to commend itself to the authorities. The Lords of the Admiralty in the course of their visit to Portsmouth in June, 1901, witnessed the working of a method of destroying submarines that had been devised by the _Vernon’s_ staff. The trials took place at a considerable distance from shore, and were confidential, and therefore no official account of what took place has appeared. Still from various sources it is possible to piece together a “story,” the moral of which (according to some writers) seems to be that a satisfactory method of destroying the enemy’s submarine boats has been found, and that henceforth the British fleet has nothing to fear from the attacks of these “marine devils.”