Halkaan ka sii qor faqradan - Holbrook wuxuu ku sugnaa Schofield Barracks, Hawaii ilaa Abriil 4, 1916 ka dibna wuxuu ahaa Quartermaster ee Fort Riley, ilaa Julaay 1916. Sanadkii 1916, wuxuu la soo shaqeeyey General John J. Pershing's Mexican Expeditionary Forces
Taliyaha dukaamada rootiga. Tani waxay ahayd isticmaalkii ugu horeeyay ee foornada ciidanka, oo uu soo saaray.