36 TlMEHRI. 



the fluvio-marine or coast deposit ; of river loam along 

 the courses of the rivers, and beyond the coast deposit ; 

 and of the valley gravel and the sand and clay deposit. 



Of these the coast deposit is the most important, 

 since here are established the various plantations of the 

 great industry of the 'colony. It extends along the 

 whole sea-board, a few feet below the level of spring 

 tides, inwards to a varying width of from 5 to 35 

 miles, where it attains a height of about 12 feet. Its 

 depth is about 100 feet, and it consists of varying layers 

 of fine sand and bluish clay, with portions of decayed 

 vegetable matter. The surface soil of this deposit con- 

 sists of a fertile dark-coloured loam on the estates ; 

 and beyond them, of a dark earth made up largely of 

 decayed vegetable remains. Many of the clay beds of 

 this deposit are suitable for brick-making, while the 

 bluish-clay below the soil, when burnt, is applied for the 

 purposes of road-making. 



The valley gravel on the great savannahs, and the 

 sand and clay deposit which underlies the coast deposit 

 at a depth of about 100 feet near the shore, are to be 

 regarded as most probably equivalents of each other. 

 The sand and clay deposit extends inland from the 

 boundary of the coast deposit, and forms a traft averag- 

 ing from 60 to 150 feet in height. The white sand of 

 this deposit, which is very abundant, is generally very- 

 pure and well adapted for glass-making, while the white 

 clay, especially that obtainable at Oreala on the Coren- 

 tyne river, seems very suitable for the manufacture of 

 porcelain and earthenware. Impure oxides of iron are 

 widely and variously distributed in beds in the alluvia 

 deposits. 



