National Geographic : 1898 Jun
1HE PHILIPPINE ISLANDS 259 largely contributed to their formation and shaping, as is testified, not only by the existence of active volcanoes, but by the still larger number of mountains which show evidences of former igneous activity, the traces of its effects on the surrounding country, and the abundance of thermal springs which are found in different localities, in which the temperature of the water ranges from 180° Fahrenheit to the boiling point. Although sit uated in a region peculiarly adapted to the growth of corals, they do not exist to any great extent on the coasts of the Philippines. Occasional traces, sometimes amounting to a fringing reef, are met with in favorable places along the west coast of Luzon and some of the other islands of the group. This scarcity of coral formation may be accounted for by the presence of volcanic fires and the occasional deluges of hot water emanating from their outlets, which prevent the growth of the polyps. All the islands are generally hilly and mountainous, but none of the summits much exceed 8,000 feet in height. The loftiest peaks are, per haps, Apo and Malindang, in Mindanao; Halcon, in Mindoro, and Mayon, in Luzon. The latter is an active volcano, which h:Ls been the scene of several disastrous eruptions within the past hundred years. As a consequence of these subterraneous forces, earthquakes are frequent and violent. An English writer says: "The destructive ravages and changes produced by earthquakes are nowhere more remarkable than in the Philippines. They have over turned mountains; they have filled up valleys; they have desolated ex tensive plains; they have opened passages for the sea into the interior and from lakes into the sea." That this is not an exaggeration is proved by historical rec ords, which contain many accounts of such disasters since the Spaniards first occupied the territory, and proofs that they have produced great geographical changes. " In that of 1627 one of the most elevated of the mountains of Cagayan disappeared. In 1675 in the island of Mindanao a passage was opened to the sea and a vast plain was emerged." The more recent of these convulsions occurred in 1863 and 1880, both of which caused great destruction of property. In the former the loss of life was greater, but the more massive buildings in the old city of Manila suffered more during the latter, the cathedral and many other edifices being completely wrecked.