18 Christmas Island— The Soil. 



that the N. and N.E. ^vind extends as far south as the island, 

 bringing with it unsettled weather. 



Unfortunately no rain - gauge ^ was taken, so that accurate 

 measurements of the rainfall were not made ; but the luxuriance 

 of the vegetation over the whole island, the fact that under fallen 

 logs the soil is generally moist, and the presence of perennial 

 springs on the east coast, are sufficient evidences that the amount is 

 large. Owing to the porous nature of the limestones and the 

 depth of the soil, there is a complete absence of standing water 

 and of marshy ground, except close to the small stream on the east 

 coast ; and though, no doubt, it is to this circumstance that the 

 island owes its extreme healthiness, still the lack of easily 

 accessible water on the higher ground is a drawback which has 

 to be reckoned with. Wherever water is found it is held up by 

 the volcanic rock, and since in many places this occurs at no great 

 depth, borings will probably give an abundant supply without 

 much difficulty. 



The Soil. 



The soil which covers the greater part of the terraces and 

 plateau, with the exception of the areas occupied by the reefs and 

 groups of pinnacles described above, is a rich brown loam, often 

 strewn with nodules of phosphate and here and there with frag- 

 ments of volcanic rock. One of the most notable features about 

 the island is the great depth to which, in many places, the soil 

 extends. For instance, near the northern angle of the plateau 

 Mr. Ross sank a well nearly forty feet without reaching the bed 

 rock, and even on the shore terrace near Flying Fish Cove a shaft 

 some fifteen feet deep was entirely in soil in which some blocks of 

 limestone were embedded. Reefs of bare limestone may occur quite 

 close to such places, and it appears therefore that the soil fills great 

 inequalities in the surface of the island. It seems impossible that 

 a soil so abundant can have resulted merely from the disintegration 

 of limestone and the decay of vegetation, and no doubt it is to a 

 considerable extent the product of the decomposition of volcanic 

 rock which must have been exposed in many places on the higher 

 land, either in consequence of the incompleteness of the limestone 

 covering of the volcanic basis of the island, or through the removal 

 of portions of that covering through denudation, or possibly in a 

 few cases through the extrusion of volcanic material in the form 

 of lava-flows or tuff beds. 



^ In Colonial Report No. 257 on tlie Cocos-Keeling and Christmas Islands, 

 paragraph 35, it is stated that owing to injuries received by the meteorological 

 instruments while in my hands, Mr. A. lloss had been unable to keep the records 

 for the previous year. This is inaccurate. The thermometer by means of which 

 Mr. Eoss recorded the temperatures in former years was never in my hands, and, 

 except perhaps a small pocket aneroid, there were not, to my knowledge, any 

 other meteorological instruments on the island. 



