But Napoleon was beforehand with them from the outset. Within twenty-four hours of the ultimatum reaching his hands he had made the opening move in the campaign: the lion, whose skin had been sold, had crouched for the fatal spring. General Mack, the Austrian Commander-in-chief, entered Bavaria on September 8. On September 1 Napoleon’s “Army of the Ocean” had struck its tents in Boulogne camp and started on its way, with plans laid that ensured Mack’s overthrow. A hundred and eighty thousand soldiers were hastening along every high-road through Hanover, Holland, and Flanders, and in eastern France, towards the great plain of central Bavaria, to deal the Austrians the heaviest and most resounding blow ever yet dealt to a modern army. Napoleon, screening his movement by means of Murat’s cavalry, sent ahead on a wide front to occupy the attention of the Austrian outposts, made a bold sweep right round Mack’s right flank. Before the Austrian general had any suspicion that there was a single Frenchman on that side of him, the entire French army had passed the Danube in his rear, and had blocked the great highway from Vienna. Napoleon at the first move had cut the Austrian line of communication with their base. He had barred the only route by which the Russians could approach to Mack’s assistance. That done, swiftly and successfully, while Mack, startled and utterly staggered at the sudden appearance of the enemy in his rear, was hurriedly facing about in confusion, to try to hold his ground, Napoleon struck at him hard. He hurled attack after attack in force on the Austrian flanking divisions, on both wings of Mack’s army, and broke them up. Taking thousands of prisoners and many guns, he drove the wreck, a disorganised mass of scared and helpless battalions, in rout to the walls of Ulm itself. Penned in there, ringed round by 100,000 French bayonets, with the French artillery pouring shot and shell into the doomed fortress from commanding heights within short range, General Mack, left now with barely 30,000 men, after a despairing interview with Napoleon, was terrorised into immediate surrender at discretion. Amid such scenes did the Eagles of the Field of Mars undergo their baptism of fire. Ever in the forefront under fire, brilliantly, time and again, did those who bore them do their duty. It was round the Eagles of Marshal Ney’s corps, “the Fighting Sixth,” that the fiercest contests of the campaign centred; and on every occasion they gained honour. In the sharp brush at the bridge across the Danube at Reisenburg, near the small town of Günsburg, on October 8, one of the opening encounters of the campaign, the Eagle of the 59th of the Line showed the way to victory. The Austrians, whom Ney surprised on the south side or right bank, retreating as the French approached, had partially broken down the bridge before Ney’s men could reach the place. [Sidenote: AT THE BRIDGE OF GÜNSBURG]