240 . APPENDIX. 



part of Palawan ; near the land this hank appears tolerably- 

 free from danger, but a little further out is thickly studded 

 with coral-reefs, which do not generally rise to the surface ; 

 some of them are very steep, whilst others have a fringe of 

 shoal- water round them. I should have thought that these 

 shoals had level surfaces, had it not been for a statement made 

 by Horsburgh, { that most of the shoals hereabouts are formed 

 of a belt of coral :' I have not coloured them. — The coasts 

 of China, Tonquin, and Cochin- China, forming the western 

 boundary of the China Sea, appear to be- without reefs : with 

 regard to the two last-mentioned coasts, I judge from an ex- 

 amination of the charts on a large scale in the atlas of the 

 Voyage of the Favourite. 



Indian Ocean. — South Keeling atoll has been specially 

 described in my first chapter. Nine miles north of it lies 

 North Keeling, a very small atoll, surveyed by the Beagle, 

 the lagoon of which is dry at low water. — Christmas Island, 

 lying to the east, is a high island, without, as I have been 

 informed, any reef. — Ceylon : a space of about 80 miles 

 in length on the south-western and southern shores of these 

 islands has been described by Mr. Twynam (Naut. Mag. 

 1836, pp. 365 and 518); and parts appear to be regularly 

 fringed by coral-reefs, which extend from a quarter to half 

 a mile from the shore. These reefs are in places breached, 

 and afford safe anchorage for the small trading craft. Outside, 

 the sea gradually deepens; there is 40 fathoms about six 

 miles off shore : I have coloured these reefs red. In the 

 published charts of Ceylon, reefs also appear to fringe several 

 parts of the south-eastern shores, coloured red. — At Venloos 

 Bay the shore is likewise fringed. North of Trincomalee 

 there are also reefs of the same character. The sea off the 

 northern part of Ceylon is exceedingly shallow ; and there- 

 fore I have not coloured the reefs which partially fringe por- 

 tions of the shores, and the adjoining islets, as well as the 

 Indian promontory of Madura. 



