Mezue ahịrịokwu na-esonụ: N'ọnwa Ọgọstụ nke afọ 1917, a họpụtara Gatley ịbụ brigadier general dị ka ọchịagha nke 55th Field Artillery Brigade, nke so na 30th Division. Mgbe nke ahụ gasịrị, a kpọfere ya n'ọchịchị nke 67th Field Artillery Brigade nke 42nd Division, nke o duziri ruo ọgwụgwụ nke agha ahụ. O sonyere na
Champagne-Marne, Aisne-Marne, St. Mihiel, na Meuse-Argonne agha na mwakpo. Site na Disemba 1917 ruo Jenụwarị 1918, Gatley duziri Ngalaba nke 30. N'afọ 1919, o nyere ndị 42nd Division iwu n'oge akụkụ nke ọrụ ya na-arụ ọrụ na Germany.