In 1888 he was sent out as captain-general to the Philippines, where he dealt very sternly with the native rebels of the Carolines, of Mindanao and other provinces.
The island of Mindanao is traversed north to south by mountain ranges, which rise in their summits to heights exceeding 4000 ft.
Farther west and south-west is the valley of the Rio Grande Mindanao, the largest river on the island, and between the lower course of this river and the south coast is a mountain range with a north-west and south-east trend.
On the east border of the south portion of the basin of the Rio Grande Mindanao is Mt Apo (10,312 ft.), an extinct volcano and the highest elevation in the archipelago.
Each of the larger islands between Luzon and Mindanao, except Samar and Bohol, is traversed longitudinally by a single mountain range with occasional spurs.