The German retreat in March, 1917, to the famous Hindenburg
line was the strategic result of this terrible battle, the tactics of
which were continuously successful and the connection between the
different arms brought to perfection, while the infantry made an
unsurpassed record for suffering and endurance and will power in such
combats as Maurepas (August 12), Clery (September 3), Bouchavesnes
(September 12)--where, when evening came, the enemy was definitely
broken--and the taking of Berny-en-Santerre, of Deniecourt, of
Vermandovillers (September 13) on the left bank, and on the right bank
the entry into Combles (surrounded on September 26), the advance on
Sailly-Saillisel and the stubborn defense of this ruined village whose
chateau and central district had already been occupied on October 15,
and in which a few houses resisted until November 12. Then, there was
the fight for the Chaulnes wood, and La Maisonnette and Ablaincourt and
Pressoire; and everywhere it was the same as at Verdun: the woods were
razed to the ground, villages disappeared into the soil, and the earth
was so plowed and crushed and martyred that it was nothing but one
immense wound.

Now, the air forces had had their part in the victory. Obliged, as they
were at Verdun, to resist the numerical superiority of the enemy, they
had thrown off the tyranny of atmospheric conditions and accepted and
fulfilled diverse missions in all kinds of weather. Verdun had hardened
them, as it had "burned the blood" of the infantry who had never known a
worse hell than that one. But as our operations now took the initiative,
the aviation corps was able to prepare its material more effectively, to
organize its aerodromes and concentrate its forces beforehand. Its
advantage was evident from the first day of the Somme offensive, not
only in mechanical power, but in a method which cooerdinated and
increased its efforts under a single command. Though this arm of the
service was in continuous evolution, more subject than any other to the
modifications of the war, and the most susceptible of all to progress
and improvement, it had nevertheless finished its trial stages and
acquired full development as connecting agent for all the other arms,
whom it supplied with information. Serving at first for strategic
reconnaissance, and then almost exclusively for regulating artillery
fire, the aerial forces now performed complex and efficient service for
every branch of the army. B