]

[Sidenote: The American sector is extended.]

With the reduction of the Marne salient we could look forward to the
concentration of our divisions in our own zone. In view of the
forthcoming operation against the St. Mihiel salient, which had long
been planned as our first offensive action on a large scale, the First
Army was organized on August 10 under my personal command. While
American units had held different divisional and corps sectors along the
western front, there had not been up to this time, for obvious reasons,
a distinct American sector; but, in view of the important parts the
American forces were now to play, it was necessary to take over a
permanent portion of the line. Accordingly, on August 30, the line
beginning at Port sur Seille, east of the Moselle and extending to the
west through St. Mihiel, thence north to a point opposite Verdun, was
placed under my command. The American sector was afterwards extended
across the Meuse to the western edge of the Argonne Forest, and included
the Second Colonial French, which held the point of the salient, and the
Seventeenth French Corps, which occupied the heights above Verdun.

[Sidenote: Large troop movements.]

The preparation for a complicated operation against the formidable
defenses in front of us included the assembling of divisions and of
corps and army artillery, transport, aircraft, tanks, ambulances, the
location of hospitals, and the molding together of all the elements of a
great modern army with its own railheads, supplied directly by our
Service of Supply. The concentration for this operation, which was to be
a surprise, involved the movement, mostly at night, of approximately
600,000 troops, and required for its success the most careful attention
to every detail.

[Sidenote: Heavy guns can reach Metz.]

The French were generous in giving us assistance in corps and army
artillery, with its personnel, and we were confident from the start of
our superiority over the enemy in guns of all calibers. Our heavy guns
were able to reach Metz and to interfere seriously with German rail
movements. The French Independent Air Force was placed under my command
which, together with the British bombing squadrons and our air forces,
gave us the largest assembly of aviation that had ever been engaged in
one operation on the western front.

[Sidenote: The First Corps.]

[Sidenote: The Third Corps.]

[Sidenote: The Fifth Corps.]

[Sidenote: Reserves.]