THE PHILIPPINE ISLANDS 
33 
the hands of the English for ten months, and was then 
restored by the Treaty of Paris. 
Much of the archipelago yet remains not only to be 
subdued by the Spanish, but to be explored. In spite of 
their three centuries of occupation many of the islands 
are very little known—some, indeed, such as Palawan 
and Mindanao, hardly at all. The coasts have been very 
imperfectly surveyed, and the hydrography leaves much 
to be desired. 
3. Geology. 
In few parts of the world are the great subterranean 
forces of the globe more in evidence than in the Philip¬ 
pine Archipelago. The islands form links in the volcanic 
chain which runs from Kamschatka southwards to join 
the even more important range which traverses the Sunda 
Islands. This chain is for the most part single, but in 
the Philippines it becomes wider. For, though in central 
Luzon the Caraballos ridge stands alone, as we progress 
southward we find it branching to form three main 
divisions. The eastern passes through Samar, Leyte, and 
eastern Mindanao to the Talautse Islands and Celebes, 
and is really the main chain. The other two, curving 
off to the west by the Calamianes, Palawan, and Banguey 
in the one case, and Negros, western Mindanao, and Sulu 
in the other, come to an abrupt end, for Borneo, as already 
stated, is non-volcanic. The volcanoes will be separately 
considered in dealing with the islands in which they 
occur. It is only necessary here to say that Mount Apo, 
with a height of 10,280 feet, according to Mr. Montano’s 
observations, and Mayon, which has been variously 
measured, and is probably not far short of 9000 feet, are 
the two most important volcanoes of the archipelago. 
D 
