This shift of the German offensive activity from the left side of the Meuse to the right is explained by the activity shown at the same time in this sector by the French. The French command was not deceived by the German tactics; they intended to husband their strength for the future Somme offensive. For them Verdun was a sacrificial sector to which they sent, from now on, few men, scant munitions, and only artillery of the older type. Their object was only to hold firm, at all costs. However, the generals in charge of this thankless task, Petain and Nivelle, decided that the best defensive plan consisted in attacking the enemy. To carry this out, they selected a soldier bronzed on the battlefields of Central Africa, the Soudan, and Morocco, General Mangin, who commanded the 5th Division and had already played a distinguished part in the struggle for Vaux, in March. On May 21 Mangin's division attacked on the right bank of the Meuse and occupied the quarries of Haudromont; on the 22d it stormed the German lines for a length of two kilometres, and took the fort of Douaumont with the exception of one salient. The Germans replied to this with the greatest energy; for two days and nights the battle raged round the ruins of the fort. Finally, on the night of the 24th, two new Bavarian divisions succeeded in getting a footing in this position, to which the immediate approaches were held by the French. This vigorous effort alarmed the enemy, and from now on, until the middle of July, all their strength was focused on the right bank of the river. [Sidenote: The bloodiest chapter of the battle.] [Sidenote: Intense barrage-fire.] This contest of the right bank began on May 31. It is, perhaps the bloodiest, the most terrible, chapter of all the operations before Verdun; for the Germans had determined to capture methodically, one by one, all the French positions, and get to the city. The first stake of this game was the possession of the fort of Vaux. Access to it was cut off from the French by a barrage-fire of unprecedented intensity; at the same time an assault was made against the trenches flanking the fort, and also against the defenses of the Fumin woods. On June 4 the enemy reached the superstructure of the fort and took possession, showering down hand-grenades and asphyxiating gas on the garrison, which was shut up in the casemates. After a heroic resistance the defenders succumbed to thirst and surrendered on June 7. [Sidenote: Thiaumont changes hands repeatedly.]