8 , ▁during ▁the ▁Spanish – American ▁War , ▁S ible y ▁commanded ▁the ▁Head quarters ▁Guard ▁of ▁the ▁IV ▁Army ▁Corps , ▁under ▁Major ▁General ▁John ▁J . ▁Co pping er . ▁He ▁again ▁served ▁as ▁the ▁Ad j ut ant ▁of ▁the ▁ 2 nd ▁U . S . ▁Caval ry ▁from ▁ 1 8 9 9 ▁to ▁ 1 9 0 0 . ▁In ▁ 1 9 0 0 , ▁S ible y ▁became ▁the ▁Ins pect or ▁General ▁of ▁the ▁Department ▁of ▁Texas , ▁and ▁remained ▁in ▁that ▁position ▁until ▁the ▁following ▁year . ▁In ▁ 1 9 0 2 ▁he ▁was ▁promoted ▁to ▁the ▁Major ▁of ▁the ▁ 1 1 th ▁United ▁States ▁Caval ry ▁Regiment . ▁He ▁was ▁then ▁made ▁the ▁Ad j ut ant ▁General ▁of ▁the ▁Department ▁of ▁Lu zon , ▁in ▁the ▁Philippines ▁from ▁ 1 9 0 3 ▁to ▁ 1 9 0 4 , ▁and ▁was ▁in ▁command ▁of ▁squad rons ▁of ▁the ▁ 2 nd ▁Caval ry ▁and ▁batt al ions ▁of ▁the ▁ 7 th ▁U . ▁S . ▁Infantry , ▁which ▁suppress ed ▁Land ron es ▁of ▁Cav ite ▁and ▁B ant ang as ▁Provin ces , ▁ 1 9 0 5 , ▁returning ▁in val ided ▁to ▁the ▁United ▁States . ▁He ▁was ▁selected ▁for ▁detail ▁to ▁the ▁General ▁Staff , ▁but ▁decl ined ▁the ▁position ▁in ▁December , ▁ 1 9 0 8 . ▁From ▁February ▁ 1 , ▁ 1 9 0 8 ▁until ▁February ▁