GARBONIFBROUS VOLCANIC ROOKS OF SOMERSET 211 
House. Lava only is met with here, the rock being a 
much weathered and highly amygdaloidal olivine basalt, 
A few yards further north, beyond the , north-easterly 
trending branch of the path, is a more continuous section 
of the volcanic series. The section is as follows : — 
feet. 
3. Pale yellow marl to top of section. .... 
2. Reddish ashy limestone, thickness doubtful, perhaps . 4-6 
Gap, no exposures ...... 3-4 
1. Thin bedded, greenish, ashy and gritty oolitic limestone, 
coarser below finer above ..... 6 
These beds dip west at 18°, and probably overlie the 
basalt just described. The volcanic series ought to crop 
out on the slopes to the west and south-west of this ex- 
posure, and we did find one minute exposure of ash a few 
yards to the south-w^est, but on the other side of the ravine 
no trace could be found of the volcanic series. 
The more easterly of the Goblin Combe exposures is a 
much better one than the more westerly. The section is 
as follows : — 
ft. in. 
3. Limestone and calcareous ash seen in the southern part 
of the exposure . . . . . . . 7 0 
2. Lenticular 'mass of coarse greenish ash with thin impersis- 
tent bands of hard limestone. These beds are seen 
in the middle part of the exposure, and in part replace 
and in part overlie band 1 . . . . . .16 
1. Red ash, with coarser, finer, and more calcareous bands . 5 0 
13 6 
The red calcareous ash (No. 1 ) is by far the most con- 
spicuous rock ; it varies much in coarseness. A remarkably 
fresh olivine dolerite occurs not in situ but as blocks 
scattered over the surface of the field to the west of the 
above exposure. 
Sir A. Geikie and Mr. Strahan give a somewhat brief 
description of these beds, mentioning that the country 
had not yet been mapped in detail. They suggest that the 
two outcrops may be really parts of the same band. They 
