Karang Posumah consists of two patches, located about 7 miles ENE and E, respectively, of Pulau Bodjo; they have depths of 4.9 to 5.5m. The SW side of the bank is very steep-to, but the NE side is more shelving. The shallowest parts may occasionally be distinguished by the swell, but seldom by breakers.
Pulau Bodjo, lying about 2 miles S of the SE extremity of Pulau Tanahbala, is densely woodedand about 150m high. It is fringed by a steep-to reef which nearly dries, extending about 0.3 mile offshore in places. A light is shown from the S side of the island.
Gosong Makasar (Makasser Reef), with a depth of 0.6m, lies about 12 miles SSE of the S extremity of Pulau Bodjo. It is easily recognized in the daytime by the high breakers on its shallow portion. The reef extends 1 mile beyond the breakers.
Sirene Reefs, one of the outermost dangers in this locality, consist of four heads, of which the westernmost and the southernmost, with 0.9m of water, sometimes break; there are depths of 1.4 and 6.9m on the other two patches.
Pulau Tamang (Pulau Temang) is an easily-identified hilly island (Area:10Km²with an average elevation of 1 m above the sea) located at the SE extremityof Teluk Batahan, about 1 mile from the coast. It is fringed by areef except at its W end, where there is a depth of 11m ...
The coastal plain between the Sungai Singkil and Udjung Tuan, about 156 miles SE, is generally narrow, being backed by mountains with numerous peaks. Ujung Tuan is a rocky point. A 175m hill, with a remarkable broad conical summit, lies close SE of the point.To Udjung Tuan, about ...
Ujung Masang is low, with a reef stretching out about 0.5 mile and should not be approached in depths of less than 31m. The Sungai Masang enters the sea at the point.