THE PHILIPPINE ISLANDS 
35 
iron ores are very abundant in Luzon and Mindanao. 
That there are extensive coal-measures in the archipelago 
there is little doubt, but they have been little exploited, 
and coal forms one of the largest imports of the group. 
The Compostela mine only turned out 700 tons in 1881. 
As yet no deep shafts have been driven, and what has 
been obtained affords very rapid combustion, and is not 
well suited for steamers. Zebu and Negros are especially 
rich in this product. Since the archipelago lies midway 
between the great coal beds of northern Borneo and 
Formosa, it is probable that the mineral will in the 
future be worked to great advantage. 
4. Climate, ebc. 
Situated between 4° and 20° of N. latitude, the 
Philippines exhibit a purely tropical climate. The mean 
temperature of Manila, deduced from data extending 
over ten years, is 81° Fahr.; the extreme minimum 59°, 
and the extreme maximum 96°. But owing to the great 
amount of sea which interpenetrates the islands, the sea 
breezes have free access to the land, and the heat is on the 
whole not excessive. At Artol, in the province of Ben- 
guet, the thermometer occasionally sinks to 38° Fahr. The 
rainfall is very great, in some places almost incessant. 
For, owing to their position and elevation, the islands 
attract the copious rains of each monsoon, and in some 
localities where the breadth of the land is much reduced, 
as at the S. Caraballos mountains and the volcano of 
Majaijay, the rainclouds of both monsoons discharge 
their contents, and torrential showers fall almost every 
day. This superabundant rainfall is a leading feature of 
the group. The rivers overflow their banks and pour 
