BY W. G. WOOLNOUGH. 479 



The basaltic rock is leached out and bleached to a kind of compact 

 "bathbrick." This bleached material forms a sort of crater, but 

 there is no native tradition of any solfataric or hot spring action. 

 Close to the base of the mound on which this occurs, there is a 

 good deal of broken-up milky, crystalline quartz. I was unable 

 to determine its origin. A second hill, rather larger than this 

 one, and distant about a mile from it, is said by the natives to 

 consist of decomposed and bleached rock similar to that described 

 above. For the last two miles to Tavua the road passes over the 

 alluvials of the Tavua River to its mouth, thus completing the 

 first section across the island from south to north. It is possible 

 that the whole of this coastal strip may represent a subsidence 

 area, and that the steep scarp which bounds it to the southwards 

 may be due to an east and west fault. 



2. From Xadarivatu to Vatukm'asa (South Coast). 



The return section from north to south was even more inter- 

 fered with by adverse meteorological conditions than the tirst 

 traverse. Starting from Nadarivatu, the road following one of 

 the branches of the Sigatoka River traverses tine to medium 

 tuffs. Over wide areas these are practically horizontally bedded. 

 Very numerous small and large volcanic cones, all more or less 

 denuded, are dotted amongst these tufl's. AVhere vents occur, 

 lava streams and plugs are developed, and the associated tuff 

 beds dip at high angles. The dips constantly change in direction. 



In some places, e.g., at IS'adrau, the lava sheets attain a great 

 thickness, probably in the neighbourhood of a specially large 

 vent. In the case mentioned, very marked prismatic structure is 

 developed, but at other points the lava is vesicular and, in some 

 cases, quite pumiceous (Plate xxxii., fig. 15). 



The rock is everywhere a tj^pical basic augite andesite. The 

 tuffs are light in colour, and, as already stated, medium to fine 

 in grain, and so friable that few of them carr}^ well. The finest 

 of them exhibit small spheroidal weathering. The coarser ones 

 are very remarkable for containing abundant ideally perfect 



