CHANGES OF LEVEL. 405 
fine-grained basalt. He states again that a broad ridge (the reef) girts 
the hills.* 
Rurutu has an elevated coral reef one hundred and fifty feet in 
height.t+ 
With regard to the other islands of these groups, Manuwaz, Actutak, 
Rarotonga, Rimetara, Tubuai, and Raivavai, the descriptions by 
Williams and Ellis appear to show that they have undergone no 
recent elevation. 
ScaTTERED Isianps 7 the latitudes between the Society and Samoan 
Groups.—These coral islands, as far as we can ascertain, are low like 
the Paumotus, excepting some of the Fanning Group north of the 
equator, and possibly Jarvis and Malden. Of the Fanning Group, 
(situated near the equator, south of the Hawaiian Group,) 
Washington Island is three miles in diameter, without a proper 
lagoon. The whole surface, as seen by us, was covered densely with 
cocoanut trees. This unusual size for an island without a lagoon 
indicates an elevation, which the height of the island, estimated at 
twelve feet, confirms. The elevation may have been do or three feet. 
Palmyra Island, just northwest of Washington, is described by 
Fanning as having two lagoons: the westernmost contains twenty 
fathoms water. Fanning’s Island, to the southeast of Washington, is 
described by the same voyager as lower than that island. ‘The 
accounts give no evidence of elevation. 
Christmas Island, still farther to the southeast, according to the de- 
scription of Cook, its discoverer, had the rim of land in some parts 
three miles wide. He mentions narrow ridges lying parallel with the 
seacoast, which “‘must have been thrown up by the sea, though it 
does not reach within a mile of some of these places.” The proof of a 
small elevation is decided, but its amount cannot be determined from 
the description. ‘The account of F. D. Bennett, (Geographical Jour. 
Vil. 226,) represents it as a low coral island. 
Jarvis Island, as seen from the Peacock, appeared to be eighteen or 
twenty feet in height, which, if not exaggerated by refraction, (we 
* Williams, Miss. Ent., p. 48, 50, 249. See also Mr. Darwin, p. 182. 
+ Williams, Miss, Ent., p. 50.—Stutchbury describes the coral rock as one hundred and 
fifty feet high. West of England Journal, ii—Tyerman and Bennett describe the island 
as having a high central peak with lower eminences, and speak of the coral rock as two 
hundred feet high on one side of the bay and three hundred on the other (ii, 102),—Ellis 
says that the rocks of the interior are in part basaltic, and in part vesicular lava, 
il. 393. 
102 
