_Defects._--The most important defects of such craft are:--
1.--The noise created by their engines, thus rendering an undetected approach to a hostile vessel impracticable.
2.--Their liability to be swamped by the explosion of the torpedo.
Of course there are many minor defects, but above are the principal ones, both of which might, to a considerable extent, be modified.
_Torpedo Boat Attacks._--It is impossible to attempt more than a very general idea of how to conduct a torpedo boat attack, as so much depends upon the circumstances, ever changing, under which each particular attack would have to operate.
The spar and the fish torpedo are the submarine weapons that can best be manipulated from boats, the towing torpedo requiring a more roomy craft than the torpedo boat generally is to operate it from with any chance of success.
_Methods of Protecting Ships from Boat Torpedo Attacks._--The principal methods that exist at the present time of protecting a ship from a boat torpedo attack are as follows:--
1.--Booms by themselves, or supporting nets hung vertically, surrounding the ship at a distance of 10 or 15 feet from the side of the vessel.
2.--A crinoline of wire, or chain, fixed by stays to the vessel's side, but capable of being lifted out of the water if required.
3.--The above methods supplemented by guard boats, and a cordon of boats.
4.--A cordon of boats, that is, boats connected at certain distances by means of hawsers, or chain cables, and at a distance of some 200 or 300 yards from the vessel, supplemented by guard boats, but without other protection.
5.--Electric lights and torpedo guns. These latter are small guns capable of penetrating the side of a torpedo boat and of being depressed at a very small angle.
As it is against these defences that torpedo boats would have to contend, therefore they have been described previous to explaining the mode of conducting a torpedo boat attack.
The first two methods of defence are of course quite impracticable when the attacked vessel is one of a blockading squadron, and it is against such vessels that a torpedo boat attack will generally be used and oftenest be successful.
In the case of a vessel forced to anchor in a harbour which is accessible to the torpedo boats of the enemy, by the application of either of the first two methods, supplemented by guard boats and electric lights, she would undoubtedly be almost impregnable against a torpedo boat attack, even were the boats armed with the fish torpedo, though she would of course not be in that state of readiness which is essential to a man-of-war's efficiency. As a general rule, no man-of-war should anchor unless absolutely necessary in the vicinity of an enemy's ports, and then should retain the power of moving in any direction in the quickest space of time possible, using the electric light and guard boats as a means of protection.