Semirara, the largest of the group, is hilly, about 512 feet high at the highest part. The west coast includes several little bays almost entirely obstructed by reefs, on the edge of which are depths of 4 3/4 to 13 fathoms; and off the town of Semirara, which stands on the top of the hill facing the largest bay, the anchorage is very bad, even for coasters. The east coast is bordered by a reef, which extends about a mile from the northeast part of the island; on coming from the north this coast of the island must not be approached within three miles until the town of Semirara bears full west. There is anchorage at the south of the island in 5 to 8 fathoms, sand, during the northeast monsoon. Good coal for steaming purposes was found on the island by Captain Villavicencio, of the Spanish navy.
Tablas Island is, mountainous, and on its northern extremity is the peak Cabezo de Tablas, 2,405 feet high; generally the coasts are clear and steep-to. Off the north end are two rocky islets, distant one cable from the coast; the larger one is clear and steep, the smaller one has rocks around it.
The west coast of Mindoro Island has no soundings off it excepting in the bays, or within one or two miles of the shore in some places. In the interior double and treble chains of mountains extend through the island, and some low points of land project from them into the sea.
Paluan Bay affords excellent shelter in the northeast monsoon, and is also a convenient place for vessels to obtain supplies when passing through Mindoro Strait. The bay is five miles wide at the entrance, of a semi-circular form, running back three miles in a northerly direction. There are no dangers in it.
A small river disembogues where good water can be obtained with facility; and on the beach there is plenty of driftwood. The coral projects one-half mile from the entrance of the river, and has 10 and 12 fathoms close to its edge.
Care must be taken when working into Paluan Bay, for the squalls come violently off the high land, and very sudden, and at night do not give the least warning.
The Calamianes are a group of high islands lying between the northeast end of Palawan and Mindoro, and extending between the parallels of 11 degrees 39 minutes and 12 degrees 20 minutes N., and the meridians of 119 degrees 47 minutes and 120 degrees 23 minutes E. Busuanga, the largest island of the group, is about 34 miles in extent NW. by W. and SE. by E., and 18 miles broad. It is very irregular in form, being indented with numerous deep bays. The islands and reefs which front its northeast side form the western side of Northumberland Strait.
These islands form, with the northern part of Palawan and the Cuyos Islands, a province, the capital of which is at Port Tai Tai. The climate of these islands is in general hot and unhealthful. Intermittent fevers and cutaneous diseases prevail, attributable, in all probability, to the great moisture and the insalubrious quality of the drinking water. All these islands are, generally speaking, hilly and broken. The industry of the locality is in collecting Salanganes (edible birds' nests), honey, and wax; but cultivation is not practiced to any great extent. The forests produce good timber for building or cabinet work.
Tara Island, when seen from the northward, shows a triple summit to its northwest end; while its southern part looks like a separate island, saddle-shaped. The island does not appear to be permanently inhabited; in March, 1885, it was occupied by parties from Busuanga, burning the grass and digging cassava.
Lagat is a small island 334 feet high, surrounded by a reef with a narrow passage between it and the reef off the south of Tara.