1836.] 



Later ite, or Iron Clay,. 



107 



tleman whose enthusiasm" says Dr. Jamieson " in the cause of science 

 was of the purest and most disinterested nature, and whose acquire- 

 ments in natural history were never surpassed by any British naturalist 

 who visited India."* 



Having thought it right to re-print Dr. T. Christie's valuable papers 

 in this Journal, I abstain from extracting his opinions here, but refer 

 to the text for the passage on the subject. 



We have seen that Buchanan describes the laterite, plainly, as a con* 

 glomerate ; and as Dr. Christie quotes that writer, as having first de- 

 scribed and designated the rock, without offering any theory of his own 

 regarding its origin, we may fairly conclude that he coincided in the 

 opinion expressed by Buchanan. 



The Rev. R. Everest, a scientific and assiduous naturalist in Bengal, 

 has described an iron stone, which I cannot but think must be the late- 

 rite, although it will be seen that, at the conclusion of the following 

 passage, the writer draws a distinction between that rock and the one 

 he is describing. 



" With the granitic soil are mixed grains of the gravel we before al- 

 luded to; and we find blocks of a reddish brown slaggy looking stone, 

 here and there, from which they have evidently been derived. These 

 pieces have, I believe, been called clay iron-stone, a mineral quite dif- 

 ferent from the clay iron-stone which is found in the English coal districts. 

 It is about the sp. gr. of 2*8, and seems to have been produced by the 

 decomposition of granite, with, perhaps, some magnetic iron. The 

 slaggy appearance is occasioned by its numerous irregular hollows, 

 mammellated inside, and, indeed, some specimens shew much of a sta- 

 lactitic form. Many grains of quartz are imbedded in it, and the quartz 

 gravel of the granitic soil often has an iron black or red coating, which 

 shows it to have had a similar origin. Those who remember the de- 

 composing state of granite in the neighbourhood of trap rocks, will 

 not be at a loss to account for this. * * * * The iron stone itself, 

 from its mammellated and imperfect stalactitic form, seems to have 

 been at least semi-fluid ; and, from its softness and earthiness, can only 

 have been a deposit from water. So that if we conceive a spring to 

 have issued from the rock, bringing with it this iron clay as a sediment, 

 which gradually agglutinated together, and hardened, we might expect 

 to find such appearances as we now see. ******** If we re- 

 collect that beds of the red clay, which have been called laterite, and I 

 believe pieces of the accompanying iron-stone, form, as it were, a 

 fringe to great part of the Bay of Bengal, covering the edge of the 

 granite of either peninsula, and lying between it and the sea, we may 



* Edinburgh new Philosophical Journal, Vol. XV. p. 156. 



