The list of questions, detailed and general, which have already been wholly or partly answered by the present campaigns might be indefinitely extended. There are hundreds of them. But if we consider only the principal ones we shall find that they fall roughly into two main categories. You have the technical questions of armament, its use and its effect; formation, and so forth; and you have the political questions. The first set are concerned with the action of human beings under particular forms of danger, and the physical effect of the weapons they will employ under the conditions of a high civilization. The second set are concerned with the action of human beings as citizens, not as soldiers. How they will face the advent of war, whether national feeling will be stronger than class feeling, whether secrecy can be preserved, and the rest. A list of the principal points in each of these sets will run somewhat as follows: In the first there were opposing schools as to-- (1) The value of modern permanent fortification and its power of resistance to a modern siege train. (2) The best formation in which to organize troops for action, and particularly the quarrel between close formation and open. (3) The doubts as to the degree of reliance which could be placed upon air-scouts, their capacity for engaging one another, the qualities that would give dominion of the air, and in particular the value of the great modern dirigible balloons. (4) The effect, method, and proportionate value of rifle fire and of the bayonet. (5) The use of field artillery; and particularly whether, after a certain degree of rapidity, still greater rapidity of fire was worth having. (6) The exact _rôle_ that would be played in modern war by the supply of certain materials hitherto unimportant and discoverable only in certain limited regions, most of them out of Europe. There are a great number of these materials, but much the most important is petrol. (7) Lastly, and by far the most vital of purely technical questions to this country, was the solution of certain opposing theories upon what is rather rhetorically called “the command of the sea” and what might more justly be called naval superiority. In the second set, the political questions, the most important were: (1) The working of the conscript and of the voluntary systems. (2) The possibility of preserving secrecy. (3) Whether mobilization would work smoothly or not in the face of class struggles supposedly formidable to national interests. (4) The action of our modern town populations under the moral strain of war. LESSONS WE HAVE LEARNT Not all of the questions, military or political, have as yet been solved by experience. Many of them are, however, already partially solved, some wholly solved. And we may consider them usefully one by one. (1) The value of permanent fortification.