When peace, especially a long peace, ends, the methods which it has introduced are the first enemies which the organised defenders of a country have to overcome. There is plenty of evidence to prove that--except, of course, in unequal conflicts between highly organised, civilised states and savage or semi-barbarian tribes--success in war is directly proportionate to the extent of the preliminary victory over the predominance of impressions derived from the habits and exercises of an armed force during peace. That the cogency of this evidence is not invariably recognised is to be attributed to insufficient attention to history and to disinclination to apply its lessons properly. A primary object of the _Naval_Annual_--indeed, the chief reason for its publication--being to assist in advancing the efficiency of the British Navy, its pages are eminently the place for a review of the historical examples of the often-recurring inability of systems established in peace to stand the test of war. Hostilities on land being more frequent, and much more frequently written about, than those by sea, the history of the former as well as of the latter must be examined. The two classes of warfare have much in common. The principles of their strategy are identical; and, as regards some of their main features, so are those of the tactics followed in each. Consequently the history of land warfare has its lessons for those who desire to achieve success in warfare on the sea. That this has often been lost sight of is largely due to a misapprehension of the meaning of terms. The two words 'military' and 'army' have been given, in English, a narrower signification than they ought, and than they used, to have. Both terms have been gradually restricted in their use, and made to apply only to the land service. This has been unfortunate; because records of occurrences and discussions, capable of imparting much valuable instruction to naval officers, have been passed over by them as inapplicable to their own calling. It may have been noticed that Captain Mahan uses the word 'military' in its right sense as indicating the members, and the most important class of operations, of both land- and sea-forces. The French, through whom the word has come to us from the Latin, use it in the same sense as Mahan. _Un_militaire_ is a member of either a land army or a navy. The 'Naval _and_ Military Intelligence' of the English press is given under the heading 'Nouvelles Militaires' in the French. Our word 'army' also came to us direct from the French, who still apply it equally to both services--_armée_de_ _terre,_armée_de_mer_. It is a participle, and means 'armed,' the word 'force' being understood. The kindred words _armada_ in Spanish and Portuguese, and _armata_ in Italian--equally derived from the Latin--are used to indicate a fleet or navy, another name being given to a land army. The word 'army' was generally applied to a fleet in former days by the English, as will be