VITI ISLANDS. 343 
cealed beneath cocoanut groves, and a thread of water may be traced 
at intervals over the verdant surface. 
The form and topographical features of the island may be best ex- 
plained by supposing it to have been a single crater. The day or two 
on shore were not sufficient to determine beyond doubt the correct- 
ness of this hypothesis. 
2. GEOLOGICAL STRUCTURE OF THE ISLANDS. 
The facts which fell under our observation, in connexion with the 
inferences that may be drawn from the specimens collected by the 
officers at the different islands of the group, indicate that the rocks 
composing the Feejee Islands, in all parts of the archipelago—ex- 
cepting those of coral composition—have a very similar character 
throughout; and that numerous more or less ancient volcanic vents, 
subaerial or subaqueous, have thrown out all the materials which 
constitute these islands. Farther exploration may require some modi- 
fication of this view, especially as the interiors of the larger islands 
remain unexplored, and even their shores have been examined in but 
few points. 
At the present day there is no active volcano in the group, and 
no tradition of one among the natives. Tarthquakes are not uncom- 
mon, one or two being usually felt every two or three years. ‘They 
are all slight, but heavier it is said, in the eastern than in the western 
part of the group. ‘The most recent appearances of eruption were 
met with on one of the eastern islands, Oneata, where there is a lava 
tract resembling the Hawauian clinker fields. 
The only trace of actual volcanic heat which the islands appear to 
contain, is found on the southeastern side of Vanua Lebu, at Savu- 
savu Bay, where a large area is covered with hot springs, the water 
of which is in constant ebullition. ‘Phe Peacock did not touch at this 
place; and for the following information [ am indebted to the officers 
of the surveying boats and the Vincennes, and especially to Lieu- 
tenant Perry and Mr. Drayton. 
These boiling springs are situated on the east side of Savu-savu 
Bay. A plain rising with a gentle slope from the water, extends 
back from the shore about three-fourths of a mile, and then passes 
into the steep declivities of a high broken ridge, running nearly 
parallel with the coast. Patches of grass, and much low, dense 
