398 COSMOS. 



New Caledonia and New Guinea, the New Hebrides and 

 Solomon's Island, Pttcairn, Tahiti and the Pauuiotu Islands, 

 traverses the great Ocean in the Southern hemisphere in a 

 direction from west to east, for a length of 5400 geographi- 

 cal miles, between the parallels of latitude of 12 and 27, 

 from the meridian of the east coast of Australia as far as 

 Easter Island, and the rock of Sala y Gomez. The western 

 portions of this crowd of islands (New Britain* the New 

 Hebrides,* Vanikoro* in the Archipelago of Santa Cruz, and 

 the Tonga-group*) exhibit at the present time in the middle 

 of the nineteenth century, inflammation and igneous action. 

 New Caledonia, though surrounded by basaltic and other 

 volcanic islands, has nevertheless nothing but Plutonic rock, OT 

 as is the case with Santa Maria 98 in the Azores, according to 

 Leopold von Buch, and with Flores and Graciosa, according 

 to Count Bedemar. It is to this absence of volcanic action 

 in New Caledonia, where sedimentary formations with seams 

 of coal have lately been discovered, that the great develope- 

 ment of living coral reefs on its shores is ascribed. The Ar- 

 chipelago of the Viti, or Feedjee Islands is at once basaltic 

 and trachytic, though distinguished only by hot springs in 

 the Savu Bay on Vanua Lebu." The Samoa group (Navi- 

 gator's Islands), north-east of the Feedjee Islands, and nearly 

 north of the still active Tonga-archipelago is likewise basal- 

 tic, and is moreover characterised by a countless number 

 of eruption-craters linearly arranged, which are surrounded 

 by tufa-beds with pieces of coral baked into them. The Peak 

 of Tafua, on the island of Upolu, one of the Samoa-group, 

 presents a remarkable degree of geognostic interest. It must 

 not, however, be confounded Avith the still enkindled peak of 

 Tafua, south of Amargura in the Tonga-archipelago. The 

 Peak of Tafua (2138 feet), which Dana first 100 ascended and 

 measured, has a large crater entirely filled with a thick forest, 



9 ? Darwin, Volcanic Islands, p. 125; Dana, p. 140. 



98 L. de Buch, Descr. des I. Can. p. 365. On the three islands here 

 named, however, phonolite and basaltic rock are also found along with 

 plutonic and sedimentary strata. But these rocks may have made their 

 a/ppearance above the surface of the sea on the first volcanic up-heaval 

 of the island from the bed of the ocean. No traces are said to have 

 been found of fiery eruptions or of extinct craters. 



99 Dana, pp. 343350. 



m Dana, pp. 312, 318, 320 and 323. 



