On the approach of the enemy Paris hastened its preparations for defence to the utmost, while in the provinces, out of reach of the German cavalry, new army corps were rapidly organized out of the few constituted regular units not involved in the previous catastrophes, the depot troops and the mobile national guard. The first-fruits of these efforts were seen in Beauce, where early in October important masses of French troops prepared not only to bar the further progress of the invader but actually to relieve Paris. The so-called "fog of war"--the armed inhabitants, francs-tireurs, sedentary national guard and volunteers--prevented the German cavalry from venturing far out from the infantry camps around Paris, and behind this screen the new 15th army corps assembled on the Loire. But an untimely demonstration of force alarmed the Germans, all of whom, from Moltke downwards, had hitherto disbelieved in the existence of the French new formations, and the still unready 15th corps found itself the target of an expedition of the I. Bavarian corps, which drove the defenders out of Orleans after a sharp struggle, while at the same time another expedition swept the western part of Beauce, sacked Chateaudun as a punishment for its brave defence, and returned via Chartres, which was occupied. After these events the French forces disappeared from German eyes for some weeks. D'Aurelle de Paladines, the commander of the "Army of the Loire" (15th and 16th corps), improvised a camp of instruction at Salbris in Sologne, several marches out of reach, and subjected his raw troops to a stern regime of drill and discipline. At the same time an "Army of the West" began to gather on the side of Le Mans. This army was almost imaginary, yet rumours of its existence and numbers led the German commanders into the gravest errors, for they soon came to suspect that the main army lay on that side and not on the Loire, and this mistaken impression governed the German dispositions up to the very eve of the decisive events around Orleans in December. Thus when at last D'Aurelle took the offensive from Tours (whither he had transported his forces, now 100,000 strong) against the position of the I. Bavarian corps near Orleans, he found his task easy. The Bavarians, outnumbered and unsupported, were defeated with heavy losses in the battle of Coulmiers (November 9), and, had it not been for the inexperience, want of combination, and other technical weaknesses of the French, they would have been annihilated. What the results of such a victory as Coulmiers might have been, had it been won by a fully organized, smoothly working army of the same strength, it is difficult to overestimate. As it was, the retirement of the Bavarians rang the alarm bell all along the line of the German positions, and that was all.