du Dragon or the Dragon's Lair), the last remaining French position on the plateau. The best-known battle, called the Second Battle of the Aisne, took place between 16 April and 25 April 1917. To soften up the German defences, General Robert Nivelle, an artilleryman by training and experience, inflicted a six-day artillery preparation involving 5,300 guns. This, of course, provided ample warning that a major French attack was coming. Then, on 16 April, seven French army corps attacked the German line along the Chemin des Dames ridge. But, Nivelle had underestimated the enemy's defensive preparations: The Germans had created a network of deep shelters in old underground stone quarries below the ridge, where their troops took shelter from the French barrage. The German positions also dominated the southerly slope over which the French attackers were progressing. On the first day, French infantry and some colonial Senegalese troops progressed to the top of the ridge in spite of intense German artillery counterfire and poor weather conditions. However, as French infantry reached the plateau, the advance was slowed and then stopped by the intense fire of a very high number of the Germans' new MG08/15 machine guns. As a result, the French took 40,000 casualties on the first day alone. Furthermore, during the following 12 days of the battle, French losses continued to rise to 120,000 casualties (dead, wounded, and missing). The final count, when the offensive was over, was 271,000 French casualties and 163,000 Germans casualties. The German defenders suffered much less, but lost some 20,000 prisoners, 40 cannons, and 200 machine guns. The high French casualty count, in so few days and with such minimal gains, was perceived at headquarters and by the French public as a disaster. Furthermore, the agonizingly slow evacuation of the French wounded also demonstrated a lack of logistical preparations. Nivelle had to resign, and the French Army became plagued by many refusals to march amounting to mutinies in several infantry divisions. This situation developed into a threat of complete disintegration. General Philippe Pétain, who had opposed this offensive, was called in to take over from Nivelle and to re-establish order. This he did without harsh collective punishments. A total of 629 men were sentenced to death, but only 28 men, who had fired weapons at their superiors, were executed. Conversely, Pétain instituted positive changes, such as longer home leaves and better food and medical/surgical assistance