135 
Before bringing the paper to a close, it may be as well to make 
a few brief remarks upon the general relation of the levels. 
_ Referring to the map, the summit line of the Polden Hills where 
the railway passes through them, may be taken almost due east 
from Dunball Railway Station, turning slightly south-east to meet 
the main road to Glastonbury, where our railway crosses it, and 
thence following the road for some miles. Cossington Park, as 
will be seen from the sections, lies almost level upon the summit, 
the permanent way of the Bridgwater Railway falling away on 
either side, the top of the hill here being broad, with a slight 
hollow in the middle. The Glastonbury Road runs along the 
- summit of a very sharp ridge, the slope on the south side being 
in some cases almost precipitous. 
With regard to the actual levels of the railway, we will begin 
with Edington Moor, which, being only 3ft. or 4ft. at the most 
above the level of the sea, we may take as our zero. The lime- 
stone, or what we infer to be such, below the banks of the 
Edington Canal, is about 34ft. down; passing southward it is 
next met with 10ft. below the surface, where it is rising in an 
angle of about 15 degrees to form the hillock between the Inner 
and Outer Moors. In this hill the strata terminate abruptly, 
giving a steep slope to the southern side, while beneath the peat 
it is again found at the site of an existing bridge (1 mile 62 chains) 
and 6ft. below moor level. Two chains further on it is touched 
again, 26ft. below moor level, and again on the extremity of the 
moor, where it is rising to form the Polden Hills. The Edington 
end of the long cutting commences 38ft. above the moor, the 
gradient of the railway rising as the line proceeds. The Rhetic 
Beds are found in the bottom of the cutting 84ft. above the level 
of the Peat Moor; the summit of the land on this side of 
Cossington Valley is 113ft. above the same level. Passing across 
the Dingle, the Rhetic Beds are found again in the base of the 
cutting, 95ft. above the level of the peat, the actual top of the 
Black Shale Beds being about 10ft. above the base of the cutting. 
