But to understand a campaign, one must seize not only the topographical positions of troops, nor only their number: one must also gauge the temper of their commanders and of the political opinion at home behind them, for upon this moral factor everything ultimately depends. The men that fight are living men, and the motive power is the soul. It is, therefore, necessary for the reader to appreciate at this terminal date, September 2-4, the moral strength of the enemy, and to comprehend in what mood of confidence the Germans now lay. With this object we must add to the story of the advance on Paris the subsidiary events which had accompanied that great sweep into the West. We must turn to the "holding up of Russia" upon the East by the Austrian forces, and see how the partial failure of this effort (news of which was just reaching the Western armies) was quite eclipsed by the splendid tidings of Tannenberg. We must see with German eyes the secondary but brilliant victory in front of Metz; we must stand in their shoes to feel as they did the clearing of Alsace, and to comprehend with what contempt they must have watched the false picture of the war which the governments and the press of the Allies, particularly in Britain, presented to public opinion in their doomed territories; and we must, in general, grasp the now apocalyptic temper of the nervous, over-strained industrialized population which is the tissue of modern Germany. Not until we have a good general aspect of that mood can we understand either the war at this turning-point in its fortunes, or the future developments which will be traced in the succeeding volumes of this series. I will, therefore, now turn to the three main elements productive of that mood in their historical order: the Battle of Metz, the Austrian operations against Russia, and, lastly, the great victory of Tannenberg in East Prussia, before concluding this volume with a summary of the whole situation in those first days of September, just before the tide turned. THE BATTLE OF METZ. The Battle of Metz, though quite subsidiary to the general operations of the war, and upon a scale which later operations have dwarfed, will be mentioned with special emphasis in any just account of the great war on account of its moral significance.