PACIFIC OCEAN. 209 



to all the islands which he visited. — Mr. Williams in his 

 Narrative, speaks of a reef going round a small island attached 

 to Oyolava, and returning again to it : all these islands have 

 been coloured red. — A chart of Rose Island, at the extreme 

 west end of the group, is given by Freycinet, from which I 

 should have thought that it had been an atoll ; but according 

 to Mr. Couthouy (Remarks, p. 43) it consists of a reef, only a 

 league in circuit, surmounted by a very few low islets ; the 

 lagoon is very shallow, and is strewed with numerous large 

 boulders of volcanic rock. This island, therefore, probably 

 consists of a bank of rock, a few feet submerged, with the 

 outer margin fringed with reefs ; hence it cannot be properly 

 classed with atolls, in which, as we have reason to believe, the 

 foundations always lie at a depth greater than that at which 

 the reef-constructing polypifers can live ; not coloured. 



Beveridge Eeef, 20° S., 167° W., is described in the Naut. 

 Mag. (May 1833, p. 442) as ten miles long in a N. and S. line, 

 and eight wide ; ' in the inside of the reef, there appears deep 

 water ; ' there is a passage near the S.W. corner : this there- 

 fore seems to be a submerged atoll, and is coloured blue. 



Savage Island, 19° S., 170° W., has been described by Cook 

 and Forster. The younger Forster (vol. ii. p. 163) says it 

 is about 40 feet high : he suspects that it contains a low 

 plain, which formerly was the lagoon. The Eev. J. Williams 

 gives 100 feet as its height, and he informs me that the reef 

 fringing its shores, resembles that round Mangaia ; coloured 

 red. 



Friendly Archipelago. — Pylstaart Island : judging from 

 the chart in Freycinet's Atlas, I should have supposed that it had 

 been regularly fringed ; but as nothing is said in the Hydrog. 

 Memoir (or in the Voyage of Tasman, the discoverer) about 

 coral-reefs, I have left it uncoloured. — Tongatabou : in the 

 atlas of the Voyage of the Astrolabe, the whole south side of 

 the island is represented as narrowly fringed by the same reef 

 which forms an extensive platform on the northern side. The 



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