Our First Corps advanced to Thiaucourt, while our Fourth Corps curved back to the southwest through Nonsard.  The Second Colonial French Corps made the slight advance required of it on very difficult ground, and the Fifth Corps took its three ridges and repulsed a counterattack.  A rapid march brought reserve regiments of a Division of the Fifth Corps into Vigneulles in the early morning, where it linked up with patrols of our Fourth Corps, closing the salient and forming a new line west of Thiaucourt to Vigneulles, and beyond Fresnes-en-Woevre.  At the cost of only 7,000 casualties, mostly light, we had taken 16,000 prisoners and 443 guns, a great quantity of material, released the inhabitants of many villages from enemy domination, and established our lines in a position to threaten Metz.  This signal success of the American First Army in its first offensive was of prime importance.  The Allies found they had a formidable army to aid them, and the enemy learned finally that he had one to reckon with.

[Illustration:  AMERICAN ATTACK ON THE ST. MIHIEL SALIENT]

[Sidenote:  Movement to cut German railway connections.]

On the day after we had taken the St. Mihiel salient, much of our Corps and Army artillery which had operated at St. Mihiel, and our Divisions in reserve at other points, were already on the move toward the area back of the line between the Meuse River and the western edge of the forest of Argonne.  With the exception of St. Mihiel, the old German front line from Switzerland to the east of Rheims was still intact.  In the general attack all along the line, the operation assigned the American Army as the hinge of this Allied offensive was directed toward the important railroad communications of the German armies through Mezieres and Sedan.  The enemy must hold fast to this part of his lines or the withdrawal of his forces with four years’ accumulation of plants and material would be dangerously imperiled.

[Sidenote:  German Army not demoralized.]

The German Army had as yet shown no demoralization and, while the mass of its troops had suffered in morale, its first-class divisions and notably its machine-gun defense were exhibiting remarkable tactical efficiency as well as courage.  The German General Staff was fully aware of the consequences of a success on the Meuse-Argonne line.  Certain that he would do everything in his power to oppose us, the action was planned with as much secrecy as possible and was undertaken with the determination to use all our Divisions in forcing decision.  We expected to draw the best German divisions to our front and to consume them while the enemy was held under grave apprehension lest our attack should break his line, which it was our firm purpose to do.

[Sidenote:  The Argonne Forest considered impregnable.]

[Sidenote:  American order of battle.]