190 
OLDER PLIOCENE PER TOD. 
[.Oh. XIV. 
b (No. 46) has been left, which was probably never so high 
as the cliff a, as it may have constituted the lower part of the 
sloping side of the original current. 
No. 46. 
Section at Castell Follit. 
A, Church and town of Castell Follit, overlooking precipices of basalt. 
B, Small island, on each side of which branches of the river Teronel flow to 
meet the Fluvia. 
c, Precipice of basaltic lava, chiefly columnar. 
d, Ancient alluvium underlying the lava-current, 
e, Inclined strata of secondary sandstone. 
From an examination of the vertical cliffs, it appears that 
the upper part of the lava on which the town is built is 
scoriaceous, passing downwards into a spheroidal basalt ; some 
of the huge spheroids being no less than six feet in diameter. 
Below this is a more compact basalt with crystals of olivine. 
There are in all about four distinct ranges of prismatic basalt, 
separated by thinner beds not columnar, and some of which 
are schistose. The whole mass rests on alluvium, ten or 
twelve feet in thickness, composed of pebbles of limestone and 
quartz, but without any intermixture of igneous rocks ; in 
which circumstance alone it appears to differ from the modern 
gravel of the Fluvia. 
Bufadors. — The volcanic rocks near Olot have often a 
cavernous structure like some of the lavas of Etna ; and in 
many parts of the hill of Batet, in the environs of the town, the 
sound returned by the earth, when struck, is like that of an 
archway. At the base of the same hill are the mouths of 
