he Kapuas, whose summits range from 3000
to 7500 ft., the latter being the height of Bukit Raja, a plateau which
divides the waters of the Kapuas from the rivers of southern Borneo; and
(3) the Muller chain, between the eastern parts of the Madi plateau
(presently to be mentioned) and the Kapuas chain, a volcanic region
presenting heights, such as Bukit Terata (4700 ft.), which were once
active but are now long extinct volcanos. The Madi plateau lies between
the Kapuas and the Schwaner chains. Its height is from 3000 to 4000 ft.,
and it is clothed with tropical high fens. These mountain systems are
homologous in structure with those, not of Celebes or of Halmahera, but
of Malacca, Banka and Billiton. From the eastern end of the Kapuas
mountains there are further to be observed: (1) A chain running
north-north-east, which forms the boundary between Sarawak and Dutch
Borneo, the highest peak of which, Gunong Tebang, approaches 10,000 ft.
This chain can hardly be said to extend continuously to the extreme
north of the island, but it carries on the line of elevation towards the
mountains of Sarawak to the west, and those of British North Borneo to
the north, of which latter Kinabalu is the most remarkable. The
mountains of North Borneo are more particularly referred to in the
portion of this article which deals with that territory. (2) A chain
which runs eastward from the central mountains and terminates in the
great promontory of the east coast, known variously as Cape Kanior or
Kaniungan. (3) A well-marked chain running in a south-easterly direction
among the congeries of hills that extend south-eastward from the central
mountains, and attaining, near the southern part of the east coast,
heights up to and exceeding 6000 ft.

_Coasts._--Resting on a submarine plateau of no great depth, the coasts
of Borneo are for the most part rimmed round by low alluvial lands, of a
marshy, sandy and sometimes swampy character. In places the sands are
fringed by long lines of _Casuarina_, trees; in others, and more
especially in the neighbourhood of some of the river mouths, there are
deep banks of black mud covered with mangroves; in others the coast
presents to the sea bold headlands, cliffs, mostly of a reddish hue,
sparsely clad with greenery, or rolling hills covered by a growth of
rank grass. The depth of the sea around the shore rarely exceeds a
maximum depth of 1 to 3 fathoms, and the coast as a whole offers few
accessible ports.