The battle of Gravelotte, or St. Privat, on the 18th completed the work so hardily begun by the 3rd German corps on the 16th. The need of driving back Bazaine's army upon Metz was pressing, and his inaction on the 17th gave time for nearly all the forces of the First and Second German Armies to be brought up to the German positions, some nine miles west of Metz, though one corps was left to the east of that fortress to hinder any attempt of the French to break out on that side. Bazaine, however, massed his great army on the west along a ridge stretching north and south, and presenting, especially in the southern half, steep slopes to the assailants. It also sloped away to the rear, thus enabling the defenders (as was the case with Wellington at Waterloo) secretly to reinforce any part of the line. On the French left wing, too, the slopes curved inward, thus giving the defenders ample advantage against any flanking movements on that side. On the north, between Amanvillers and Ste. Marie-aux-Chênes, the defence had fewer strong points except those villages, the Jaumont Wood, and the gradual slope of the ground away to the little River Orne, which formed an open glacis. Bazaine massed his reserves on the plateau of Plappeville and to the rear of his left wing; but this cardinal fault in his dispositions--due to his haunting fear of being cut off from Metz--was long hidden by the woods and slopes in the rear of his centre. The position here and on the French left was very strong, and at several parts so far concealed the troops that up to 11 A.M. the advancing Germans were in doubt whether the French would not seek to break away towards the north-west. That so great an army would remain merely on the defensive, a course so repugnant to the ardour of the French nature and the traditions of their army, entered into the thoughts of few. Yet such was the case. The solution of the riddle is to be found in Bazaine's despatch of August 17 to the Minister of War: "We are going to put forth every effort to make good our supplies of all kinds in order to resume our march in two days if that is possible[41]." That the army was badly hampered by lack of stores is certain; but to postpone even for a single day the march to Verdun by the northern road--that by way of Briey--was fatal. Possibly, however, he hoped to deal the Germans so serious a blow, if they attacked him on the 18th, as to lighten the heavy task of cutting his way out on the 19th. [Footnote 41: Bazaine, _Rapport sommaire, etc._ The sentence quoted above is decisive. The defence which Bazaine and his few defenders later on put forward, as well as the attacks of his foes, are of course mixed up with theories evolved _after_ the event.]