[Illustration: _Below_--A party of Serbian officers trying the effects
of gas while on a visit to the Western front. They entered a British
trench filled with gas for practice purposes, and are seen adjusting
their gas masks for protection. (_British Official Photo, Copyright by
U. & U._)]


[Illustration: _Top_--A great Australian howitzer in action
in France under a camouflage screen. Note the size of shells, which
require four men to handle. (_Australian Official Photo; copyright, U. &
U._)

_Bottom_--American Army Postoffice in France on Mothers' Day, 1918.
Letters and packages from the folks back home are the American soldiers'
greatest comfort on the battle front. (_Copyright, Committee on Public
Information_.)]


[Illustration: An American battery of howitzers ready to
fire upon the Huns from the ruins of a town in France. This was one of
the first United States official photographs of the American advance
in the Argonne, a district that is not all forest by any means, but
comprises much cultivated territory and many towns and villages that
have been wrecked by ruthless German fire. (_Photo by Signal Corps,
U.S.A_.)]


[Illustration: CHARGE OF THE BRITISH 9TH LANCERS ON A GERMAN
BATTERY DURING THE BATTLE OF MONS