76 EXPEDITION TO JAPAN. 



and is rounded down as if it had been exposed to the attrition of the sea or some other cause ; 

 it is 576 feet high from the level of the sea. From it, a high ridge called the Backbone ex- 

 tends to the head of the bay, and then branches out in several directions on the southern part 

 of the island. Half a mile to the northeast is another peak (B), but it is not more than 250 

 feet high ; its formation and general appearance are similar to the last. Near the most north- 

 eastern point of the island is a third peak (0), which rises rather more abruptly than the other 

 two, to the height of 800 feet ; it is covered almost to its summit with jungle-weed and a thick 

 undergrowth of trees. From it a mountain ridge extends in an easterly direction towards Buck- 

 land island, and is the boundary to a plain which begins at the base of the peaks just described, 

 and extending to the sea on the north. The plains sloping towards Port Lloyd are traversed 

 at several places by deep ravines, which, during rainy weather, serve as outlets to the mountain- 

 streams, but are entirely dry during the summer months. Most of them contain large con- 

 glomerate boulders, which at first sight appear to be sandstone, but on a close investigation 

 prove to be several kinds of trap-rock. They, no doubt, were rolled down from the broken 

 peaks, and were worn round by the attrition of the water and sand to which they have for ages 

 been exposed. That portion of the island which is between the head of the bay and Buckland 

 straits is not more than about one mile wide, and differs in some respects from that already 

 noticed ; it is not so fertile, the vegetation is less luxuriant, and the rocks present a different 

 character. Near the central part is what I conceive to be the crater of an ancient and extinct 

 volcano, as many facts tend to demonstrate. The form of the surrounding hills is peculiar ; 

 large masses of scorias and cinders are found all around ; along the sea are beds of hardened 

 lava resting upon each other, occasionally interstratified with layers of sand, scorias, and cin- 

 ders. The trees are small and stunted, and the ground in many places barren and unproduc- 

 tive, in consequence of the soil being thin and readily dried out during long droughts. After 

 this, small valleys, plains, and hills of various heights, extend to the east and north, when the 

 island again becomes much wider The two peaks called the Paps here rise, the one to 1,000, 

 and the other to 1,100 feet above the level of the sea. On the one side, at the base, is a deep 

 valley, which is about a mile in length and half a mile in breadth, and a stream of running water 

 passes through the middle of it. On the other or north side is a very deep ravine, with precipi- 

 tous trap-rocks rising up hundreds of feet, and at the bottom precipices 20 and 30 feet high, 

 over which a small stream of water falls. On the southeast of the mountains large sloping 

 plains are formed, which extend nearly to Fitton's bay, and are covered with beautiful forests 

 of palms. 



The whole island is, undoubtedly, of volcanic origin, as all the geological facts which can be 

 collected tend to prove, and its general conformation and lines of hills give strong evidence. 

 Ancient craters at this time can readily be traced ; trap-rock forms its basis, and also the 

 highest peaks ; basaltic dykes passing through beds of sand ; scoriae and cinders, amygdaloid 

 and greenstone, in considerable quantities, are found at many places ; and I have succeeded in 

 tracing strata of old lava along the sea-coast, and other parts where deep sections of rock were 

 exposed. In a ravine, running from peak 0, we discovered a sulphur spring, the odor and taste 

 of which gave the strongest proof that it was highly impregnated with hydro-sulphuric gas. 

 Iron pyrites (bisulphuret of iron) in abundance are also found at several places. The vegeta- 

 tion of this island is such as is found in nearly all volcanic countries under similar latitudes. 

 Its luxuriance appears to be in consequence of the mineral ingredients, iron, potash, soda, 

 lime, alumina, and silica, being in such proportions as to supply its demands. 



