Dr. Nugent on the Geology of the Island of Antigua. 467 
and other buildings in that vicinity. The common idea is, that the 
colour of this stone is owing to an impregnation of copper, but it is 
more probably owing to manganese and iron. Some varieties of 
this formation have a blueish colour, and some a yellowish hue ; 
others are quite even, and homogeneous in their composition, and 
some quite granular, slaty and shivery. The conglomerate character 
of this rock is derived from its having imbedded and incorporated 
with it, numerous fragments of all sizes of petrified wood, chert 
with coralline impressions, agate, jasper, blood-stone, amygdaloid, 
greenstone, clay and horn-stone, porphyry, porphyry-slate, lava, and 
other substances.* It is not every stratum of the family, however, 
which has this conglomerate character, some being quite homo- 
geneous in their composition, having a dull earthy fracture, and 
some looking like a pale yellow free-stone, as at Scot’s-hill. The 
quantity and variety of the substances included, especially of petri- 
fied wood, is most astonishing. These siliceous woods are all 
apparently of the tropical kinds, and those of the palm tribe are 
among lhe most common. 
The conglomerate does not always retain a stratified form ; it is 
not the case in Five Island division, and there the outline of the 
hills is different, partly from this cause, and partly from the pre- 
* All these are remarkably presented together in the Savannah, Gunthorpe’s pasture, 
and other places. At Drew’s hill, is a mass of wacke porphyry, with a strong vein of 
white sulphate of barytes. The coralline flints of these beds may be very readily distin- 
guished from those of the marl formation. The madrepores are different ; and in the latter 
case are more perfect and transparent, and have more of the varied character of agate. 
+ I have found several times, petrified, the bulbous part of the cocoa nut palm, where 
it emerges from the ground, and with the radicles which lace it thereto. One of the 
most remarkable specimens of fossil wood I met with in the pasture near Paynter’s 
estate, the trunk of a tree about twelve feet in length and as many inches in diameter, 
rent crosswise asunder, but all the parts lying contiguous to one another. 
