It will have been gathered from the preceding pages that the tactics adopted by the Germans north of the Aisne were tactics designed to wear down the British force. No troops, it was supposed, could, even if they survived, withstand such an experience as that of the eight days from September 20 to September 28. Their lines pounded during all the hours of daylight by heavy shells, and assaulted during the hours of darkness by masses of infantry, the British force ought, upon every German hypothesis of modern warfare, to have been either driven back, or broken to pieces. The theory had proved unsound. To say nothing of the enormous monetary cost of the ammunition used, the attacks had turned out appallingly wasteful of life. The best troops of the Prussian army had been engulfed. In this savage struggle, between 13,000 and 14,000 British soldiers had been killed or wounded. What the losses were on the side of the Germans we do not know, for their casualties in any particular operations have not been disclosed. If, however, their losses were on anything like the same scale as those at Mons and at Cambrai, the casualties must have been severe in the extreme. That they were severe is certain. The tactics adopted on the Aisne were not yet substantially different from the tactics followed in the earlier battles. At this stage of the campaign, the Germans still held to the principle that for victory hardly any price was too high. Remembering at the same time that neither lives nor money are sacrificed by Germany without what is considered good cause, it becomes necessary when there are heavy sacrifices to search for the most adequate and assignable reason. In this instance, the search need not go far. After the first week of the battle, the enemy were not merely defending their stronghold, they were attempting to carry out an offensive, and that offensive had two objects. One was the scheme of operations against the left of the Allied line. The other was the recapture of Rheims. Consider how a defeat of the British force must have affected the situation. On the one hand, it would have enabled the Germans to push back the 6th French army upon Paris; on the other, it would have compelled the French to evacuate Rheims. Now Rheims was clearly at this time the key of the Allied position. The roads and railways converging upon the city made it an advanced base of the first importance. Driven out of Rheims, the Allies would have found their communications between Noyon and Verdun hopelessly confused. Neither reinforcements, nor munitions, nor supplies could have been brought up save by difficult and circuitous routes. A general retreat must have become imperative, and all the advantages arising from the recent victory on the Marne have been lost.