GEOLOGY AND MINERALOGY. 
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Cellular Lava. — Many varieties. 
Trachyte. — s.G. 2 523. 
Ditto, passing into white clay ; below Bamboo Hedge, at 
Ladder Hill, &c. — s.g. 2 - 75. 
Lamelliferous greystone dike from immediate proximity to augite 
and other dikes ; Manatee Bay. 
Laterite. — Various colours and degrees of hardness, between beds 
of Lava. 
Volcanic tufa, between layers of lava. 
Volcanic breccia or pudding stone ; Ladder Hill, &c. 
Volcanic scoriaceous agglomerate. 
Compressed tufaceous rock. 
Compressed tufaceous rock, coloured red by oxide of iron, and 
containing augite, &c. ; Bed Quarry, Woodlands, Bock 
Cottage, Buperts ; a compact variety, much hardened by 
plutonic action and pressure between the thick layers of 
lava, is largely used as a dressed stone for building pur- 
poses. A coating of mortar on the exposed face preserves 
it from atmospheric action. The basalts and harder rocks 
are used chiefly for rubble building and for macadamizing 
roads. 
Agglomerate rocks formed of masses of scoriae and volcanic ashes 
lying between the beds of laterite and lava. 
Porphyritic lava, containing disseminated crystals of carbonate 
of lime; Holdfast Tom. 
Volcanic scoria? and pumice ; High Knoll. 
Volcanic ashes. 
Possiliferous-like masses of scoriae ; High Knoll. 
Augite rock ; Turk’s Cap, Manatee Bay, &c. 
Siliceous rock — Flint, coloured by oxide of iron, chiefly in pebbles 
on seashore at Manatee Bay. — s.g. 2 - 60. 
Dolerite, containing disseminated augite and chrysolite, partially 
amygdaloidal and zeolitic. The cavities containing crystallized 
cbabazite. — s. g.2‘85. Dike on crater edge above Thomp- 
son’s Wood. 
Bed porphyritic lava from dike at Prosperous Bay. 
Trachyte dikes, very laminated, exhibiting, through colouring 
by oxide of iron, a false appearance of stratification. — s.g. 
2 64. Prosperous Bay. 
