There are three active volcanoes on the New Hebrides—the mighty double crater on Ambrym, the steep cone of Lopevi, and the volcano of Tanna. There is a half-extinct volcano on Venua Lava, and many other islands show distinct traces of former volcanic activity, such as Meralava and Ureparapara, one side of which has broken down, so that now there is a smooth bay where once the lava boiled.
Rivers are found only on the larger islands, where there are volcanic rocks. In the coral rocks the rain-water oozes rapidly away, so that fresh-water springs are not frequently found, in spite of very considerable rainfall.
Climate
The climate is not hot and very equable. The average temperature in Efate in 1910 was 24.335° C.; the hottest month was February, with an average of 27.295°, the coolest, July with 11.9° C. The lowest absolute temperature was 11.9° C. in August, and the highest 35.6° C. in March. The average yearly variation, therefore, was 5.48°, and the absolute difference 23.7°.
The rainfall is very heavy. In December the maximum, 564 mm., was reached, and in June the minimum, 22 mm. The total rainfall was 3.012 mm., giving a daily average of 8.3 mm.
These figures, taken from a table in the Neo-Hebridais, show that the year is divided into a cool, dry season and a hot, damp one. From May to October one enjoys agreeable summer days, bright and cool, with a predominant south-east trade-wind, that rises and falls with the sun and creates a fairly salubrious climate. From November to April the atmosphere is heavy and damp, and one squall follows another. Often there is no wind, or the wind changes quickly and comes in heavy gusts from the north-west. This season is the time for cyclones, which occur at least once a year; happily, their centre rarely touches the islands, as they lie somewhat out of the regular cyclone track.
A similar climate, with but slightly higher temperature, prevails on the Santa Cruz Islands.
Flora and Fauna
The vegetation of the New Hebrides is luxurious enough to make all later visitors share Quiros’ amazement. The possibilities for the planter are nearly inexhaustible, and the greatest difficulty is that of keeping the plantations from the constant encroachments of the forest. Yet the flora is poorer in forms than that of Asiatic regions, and in the southern islands it is said to be much like that of New Caledonia.
