ited lengths of these volcanic belts is about ninety degrees,
or one-fourth of the entire circumference of the globe. Their width is
about fifty miles; but, for a space of two hundred miles on each side
of them, evidences of subterranean action are to be found in recently
elevated coral-rock, or in barrier coral-reefs, indicating recent
submergence. In the very centre or focus of the great curve of volcanoes
is placed the large island of Borneo, in which no sign of recent
volcanic action has yet been observed, and where earthquakes, so
characteristic of the surrounding regions, are entirely unknown. The
equally large island of New Guinea occupies another quiescent area,
on which no sign of volcanic action has yet been discovered. With the
exception of the eastern end of its northern peninsula, the large and
curiously-shaped island of Celebes is also entirely free from volcanoes;
and there is some reason to believe that the volcanic portion has once
formed a separate island. The Malay Peninsula is also non-volcanic.

The first and most obvious division of the Archipelago would therefore
be into quiescent and volcanic regions, and it might, perhaps, be
expected that such a division would correspond to some differences in
the character of the vegetation and the forms of life. This is the case,
however, to a very limited extent; and we shall presently see that,
although this development of subterranean fires is on so vast a
scale--has piled up chains of mountains ten or twelve thousand feet
high--has broken up continents and raised up islands from the ocean--yet
it has all the character of a recent action which has not yet succeeded
in obliterating the traces of a more ancient distribution of land and
water.

Contrasts of Vegetation.--Placed immediately upon the Equator and
surrounded by extensive oceans, it is not surprising that the various
islands of the Archipelago should be almost always clothed with a forest
vegetation from the level of the sea to the summits of the loftiest
mountains. This is the general rule. Sumatra, New Guinea, Borneo, the
Philippines and the Moluccas, and the uncultivated parts of Java and
Celebes, are all forest countries, except a few small and unimportant
tracts, due perhaps, in some cases, to ancient cultivation or accidental
fires. To this, however, there is one important exception in the island
of Timor and all the smaller islands around it, in which there is
absolutely no forest such as e