This page has been validated.
Chap. IV.]
FOSSIL TREES
71
1840
strewed about and piled around the sides of the cone. From this point we obtained a most commanding and extensive view of the neighbouring country, of a considerable portion of its northwestern coast, and of the adjacent islands.
On the south side of the harbour is the extraordinary rock noticed by Cook, and which forms so conspicuous an object in his accurate, drawing of this place. It is a huge mass of basalt much more recent than the rock on which it rests, and through which it seems to have burst in a semi-fluid state. It is upwards of five hundred feet thick, and rests upon the older rock at an elevation of six hundred feet above the level of the sea; and it was between these rocks of different ages that the fossil trees were chiefly found, and one exceeding seven feet in circumference was dug out and sent to England. Some of the pieces appeared so recent that it was necessary to take it in your hand to be convinced of its fossil state, and it was most curious to find it in every stage, from that of charcoal lighting and burning freely when put in the fire, to so high a degree of silicification as to scratch glass. A bed of shale, several feet in thickness, which was found overlaying some of the fossil trees had probably prevented their carbonization when the fluid lava poured over them. A still more extraordinary feature in the geology of this island is the numerous seams of coal, varying in thickness from a few inches to four feet, which we found imbedded in the trap rock; the positions of two of