APPENDIX. 231 



shoal, and as spits of sand and gravel (^Horsburgh, vol. ii. 

 p. 450) extend far out from them, it is impossible to draw 

 any inferences regarding the nature of the reefs. 



China Sea. — Proceeding from north to south, we first 

 meet the Pratas Shoal (lat. 20° N.) which, according to 

 Horsburgh (vol. ii. p. 335), is composed of coral, is of a 

 circular form, and has a low islet on it. The reef is on 

 a level with the water's edge, and when the sea runs high, 

 there are breakers mostly all round, " but the water within 

 seems pretty deep in some places ; although steep-to in 

 most parts outside, there appear to be several parts where 

 a ship might find anchorage outside the breakers ; " coloured 

 blue. — The Paracells have been accurately surveyed by 

 Capt. D. Ross, and charts on a large scale published : but few 

 low islets have been formed on these shoals, and this seems 

 to be a general circumstance in the China Sea; the sea 

 close outside the reefs is very deep ; several of them have 

 a lagoon-like structure; or separate islets {Prattle, Robert, 

 Drummond, etc.) are so arranged round a moderately 

 shallow space, as to appear as if they had once formed 

 one large atoll. — Bombay Shoal (one of the Paracells) has 

 the form of an annular reef, and is "apparently deep with- 

 in ; " it seems to have an entrance (Horsburgh, vol. ii. 

 p. 332) on its west side ; it is very steep outside. — Discovery 

 Shoal, also, is of an oval form, with a lagoon-like space 

 within, and three openings leading into it, in which there 

 is a depth from two to twenty fathoms. Outside, at the 

 distance (Horsburgh, vol. ii. p. 333) of only twenty yards 

 from the reef, soundings could not be obtained. The 

 Paracells are coloured blue. — Macclesfield Bank: this h 

 a coral-bank of great size, lying east of the Paracells ; some 

 parts of the bank are level, with a sandy bottom, but, 

 generally, the depth is very irregular. Tt is intersected by 



