A DAY AT CHRISTMAS ISLAND. 1 25 



cliffs rising one above the other, shewing that the island has 

 been slowly and gradually elevated from the sea bottom, 

 Where the upper surface is exposed it weathers into pinnacles 

 and curiously shaped angular projections, and though weather- 

 ing externally into holes, the inner portions are usually homo- 

 geneous. I did not see any fossils in it, but the distinguish- 

 able remains of shells and coral would probably be found, if 

 sought for. 



Exactly similar rock occurs in Fernando de Noronha, an 

 island lying off the East coast of Brazil, which I visited in 1887, 

 and with which Christmas Island has many points in common. 

 This coral rock has been described by Mr. BRANNER in some 

 notes on the petrology of Fernando de Noronha, published 

 lately in the American Journal of Science as being derived from 

 sand-dunes hardened by carbonate of lime. He shows, how- 

 ever, by analysis that it consists almost entirely of carbonate 

 of lime with a very small proportion of silica which would at 

 once negative that suggestion. Furthermore, it was quite 

 easy to find at Fernando de Noronha spots where the coral= 

 reef, which was still growing at the outer edge in the sea, passed 

 into the compact ringing rock with no distinguishable organic 

 remains in it. It is true that on Fernando de Noronha there 

 are sand-dunes which might, and indeed had in one place, be= 

 come hardened more or less into rock, not much resembling, 

 however, the limestone, but in Christmas Island there is no 

 level place on which could develope sand-dunes sufficiently 

 extensive to form the immense mass of rock of which the great- 

 er portion of the island consists. 



On our return from Christmas Island to Singapore we 

 stopped for an hour or two at Anjer Point in Java, opposite the 

 volcanic island Krakatau, of which so large a portion was 

 destroyed by an eruption a few years ago. Anjer Point was 

 then struck by an enormous wave which overthrew the light- 

 house and caused a great loss of life. On the shore near the 

 remains of the old light-house are some very large blocks of 

 stone which, I was informed, were thrown up there from Kra- 

 katau, when in eruption. However, on examining them, I 

 found they were masses of ordinary coral reef, which were pro- 

 bably thrown up from the sea by the large wave. They were 



