Page:Transactions of the Geological Society, 1st series, vol. 1.djvu/409

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with ease. This stratum of red lava is of a short continuance. Passing a small brook, it dips rapidly to the westward, and in its place. the grey lava is found in a confused though sometimes prismatic form, and rises from the beach while the red lava still runs along the surface to the height of near 100 feet, the top being covered with a thick scoria.

There is also in the vicinity of Funchal, to the eastward of the town, a fall of water, which, independent of the romantic beauty of the situation, merits being visited on account of the exposure of the two strata of lava in their relative position. The hills are composed wholly of lava, sometimes of a confused, sometimes of a prismatic formation, the red and grey lavas being visible on both sides of the valley. Near the head of it, a short distance from the cascade, the red stratum is at the bottom, and about 60 feet higher it re-appears, and again, about 200 feet higher, alternating with the grey lava. The upper red lava dips rapidly to the south, and the strata are disposed in the following manner.

Upper Red. Grey lava. Lower red

The rock, down which the cascade falls, is also intersected with a red stratum of about 3 feet wide, that traverses it, and dips to the westward, and is broken off by a broad dyke of grey lava. It appears about 30 feet higher, and dips again to the westward. The substance of the red rock in this place is hard, and it breaks into a columnar form, being