208 Dr. Rink on the 



the sea, and only covered with the soil formed by the decomposing 

 effects of the atmosphere, and supporting a more or less vigorous 

 primitive vegetation. But on Kamorta, Nangkoory and Trinket, 

 which are not so high in comparison to their size as those above 

 mentioned, the ground is rather undulating, and forming a range of 

 less significant hills and valleys ; the Plutonic rocks certainly appear 

 on different points of the Islands, but those parts which are lying 

 between these points are covered with beds of Neptunic origin. These 

 beds consist chiefly of a singular soft claystone of a grey, and some- 

 times of a white colour; when examined with the microscope, it 

 seems to have a very uniform composition, containing only some 

 white, sometimes pipe-formed spots, and no mica at all. It resists 

 the action of strong acids, and when dissolved by melting with 

 carbonate of soda, it exhibits some oxide of iron, magnesia, and 

 alumine, joined with a large quantity of silex. The claystone itself 

 is very light and spongy, absorbing water and adhering to the tongue : 

 nearly all the hills formed by it appear naked, and covered only 

 with low grass instead of tree jungle ; and this seems to prove, that 

 they are not fertile nor fit for cultivation, which also was to be 

 expected from a soil containing no mica, and no sand to make 

 it loose and porous and render it accessible for the chemical action 

 of the atmosphere. The claystone is not schistous at all, but 

 contains in several spots many clefts filled with fine crystals of 

 gypsum and thin plates of red ironstone, both formed by the action 

 between carbonate of lime and a solution of sulphate of iron from 

 oxy dated pyrites. This gypsum is again acted on by the magnesian 

 earth of the clay, which forms an efflorescence of sulphate of mag- 

 nesia on several cliffs exposed to the open air. The lower parts 

 of this claystone are always traversed by a conglomerate or con- 

 glomerous sandstone, composed of fragments of the above mentioned 

 Plutonic rocks, which appear on different points of the Island ; and 

 at some places, principally most near the Plutonic hills, the con- 

 glomerate is by far the prevalent. These places are also generally 

 covered with the most impenetrable jungle, and seem to contain 

 a much more fertile soil. The composition of the clay as well as 

 that of the conglomerate seems to prove, that both are formed during 

 the progress of the ascent of the Plutonic rocks out of the sea. The 



