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GLOUCESTER, DORSET, AND SOMERSET. O
bring that about), there would not be much difference between the
Ham-Hill section and several other sections near Sherborne.
Fig. 2. — Comparative Sections of Beds at Ham Hill and
Babylon Hill.
Ham Hill.
Babylon Hill.
Bedded
brown
sandy -
free-
stones.
I te
Dorset Cephalopoda-bed.
^
Brown sands,
with occasional
blocks and
bands of sandy
freestones con-
taining Oolitic
fossils.
- " i. 's , ,r T ' i ' .
Position of Gloucestershire
Cephalopoda-bed.
Ham Hill has always been a puzzle to the geologist ; but if we
place it on the same horizon as the so-called " Lias Sands " at Brad-
ford, the difficulty is at once cleared up.
Mr. Moore, in his paper " On the Middle and Upper Lias of the
South-west of England," speaking of Ham Hill says : —
" The workable freestone at this spot is 58 feet thick, and almost
entirely composed of comminuted shells, united by an irony cement,
and is a remarkable deposit ; for though attaining so considerable a
thickness, it does not appear to be represented in any other locality.
It has been largely worked for centuries, and yields a very excellent
stone, of a light-brown colour, due to the presence of carbonate of
iron, an analysis of the deposit proving it to contain 14 per cent of
metallic iron " *.
The best Gloucestershire equivalent of this bed is to be seen in
the straight wall of rock at Crickley Hill, which latter section we
consider the equivalent of the freestone-beds at Ham Hill, and the

• Proceedings of the Somersetshire Archaeological and Natural-History