her, with a general altitude of 3200 ft. In the south
it joins the Peak of Bonthain, or Lompo-battang, a great volcanic mass
10,088 ft. high. In the east central part of the island the mountain
Koruve exceeds 10,000 ft., and is supposed to be the highest in the
island. An alluvial coast plain, 7 to 9 m. wide, stretches along the
foot of the western chain, and between the two chains is the basin of
the Walannae river, draining northward into Lake Tempe. Little is known
of the orography of the eastern peninsula. At the base of the
south-eastern there is another large lake, Tovieti. In this peninsula
there are parallel ranges on the east and west flanks. The trench
between them is partly occupied by the vast swamp of Lake Opa.

The rivers of the narrow mountainous peninsulas form many rapids and
cataracts; as the Tondano, draining the lake of the same name to the
north-west coast of Minahassa at Menado; the Rano-i-Apo, flowing over
the plateau of Mongondo to the Gulf of Amurang; the Poigar, issuing from
a little-known lake of that plateau; the Lombagin, traversing narrow
canons; and the river of Boni, which has its outfall in the plain of
Gorontalo, near the mouth of the Bolango or Tapa, the latter connected
by a canal with the Lake of Limbotto. All these rivers are navigable by
praus or rafts for only a few miles above the mouth. In central Celebes,
the Kodina flows into Lake Posso, and the Kalaena discharges to the Gulf
of Boni; the Posso, navigable by _blottos_ (canoes formed of hollowed
tree-trunks), is the only river flowing from the lake to the Gulf of
Tomini. The rivers of the southern peninsula, owing to the relief of the
surface, are navigable to a somewhat greater extent. The Walannae flows
into Lake Tempe, and, continued by the Jenrana (Tienrana), which
discharges into the Gulf of Boni, is navigable for small boats; the
Sadang, with many affluents, flows to the west coast, and is navigable
by _sanpans_. The Jenemaja is a broad river, navigable far from the
mouth. The coasts of Celebes are often fertile and well populated; but,
as shown by the marine charts, many sand, mud and stone banks lie near
the shore, and consequently there are few accessible or natural ports
or good roadsteads.

_Geology._--The geological observations on Celebes are too scattered
to reveal its structure. The greater part of the island seems to be
formed of gneiss and other crystalline rocks. These are overlaid by
conglomerates, l