If it be hoped that a localised force will render coast-wise traffic safe from the enemy, a little knowledge of what has happened in war and a sufficiently close investigation of conditions will demonstrate how baseless the hope must be. Countries not yet thickly populated would be in much the same condition as the countries of western Europe a century ago, the similarity being due to the relative scarcity of good land communications. A part--probably not a very large part--of the articles required by the people dwelling on and near the coast in one section would be drawn from another similar section. These articles could be most conveniently and cheaply transported by water. If it were worth his while, an enemy disposing of an active cruising force strong enough to make its way into the neighbourhood of the coast waters concerned would interrupt the 'long-shore traffic' and defy the efforts of a localised force to prevent him. The history of the Great War at the end of the eighteenth century and the beginning of the nineteenth teems with instances of interruption by our navy of the enemy's coast-wise trade when his ocean trade had been destroyed. The history of the American War of 1812 supplies other instances. The localised defence could not attempt to drive off hostile cruisers remaining far from the shore and meaning to infest the great lines of maritime communication running towards it. If those cruisers are to be driven off at all it can be done only by cruising ships. Unless, therefore, we are to be content to leave our ocean routes, where most crowded and therefore most vulnerable, to the mercy of an enemy, we must have cruisers to meet the hostile cruisers. If we still adhere to our localised defence, we shall have two distinct kinds of force---one provided merely for local, and consequently restricted, action; the other able to act near the shore or far out at sea as circumstances may demand. If we go to the expense of providing both kinds, we shall have followed the example of the sage who cut a large hole in his study door for the cat and a small one for the kitten.