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FOREST MARBLE. 
Soil.-™ -Colour, dull dark brown. 
Consistence , tenacious, sticky, or adhesive, and difficult to plough when wet; when 
dry loose or dusty ; thinly strewed with flat stones. 
Subsoil, gray; broad flat stones, with clay or tenacious earth between : in some parts a whitish 
blue indurated marl between. 
Stratum, gray coarse grained stone, some of which on closer inspection appears to be composed 
of dark coloured shells, interspersed with whiter grains of ova. Bivalve shells most 
common to the thick beds ; univalve to the thin. Decomposed pyritical wood often gives 
a partial redness; and some of the joints have a reddish tinge. 
Some of the most solid beds in different parts of its course are raised and polished for 
marble. Much of the stone is brown on the outside, and gray or blue within. 
Excavations, not very deep; sometimes dry, but more commonly in low ground hold water, 
particularly in winter. 
This rock is distinctly separated from the preceding by a course of clay, below which a sand 
and sandstone, alternating with some of these shelly beds, renders the top of this rock less 
distinct. The bottom of it rests upon clay, which is the covering of the upper Oolite rock, and 
which occasionally contains thin gray lamina of stone, like some of the forest marble beds, 
composed of ova, and small turbinated shells compact enough to receive a polish. The beds 
of the rock which rise large and sound enough for slabs and marble chimney pieces, lie gene- 
rally in clay, or in pits which hold water. Where the separating clay is thin, the water of this 
rock sinks into the more capacious joints of the Oolite rock beneath, by apertures called 
swallow-holes, which are very numerous in the course of this Stratum, from Bath by Tetbury, 
and other parts of the Cotswold Hills, to the forest of Whichwood, from which place and its 
adjacent quarries it has received the name of Forest Marble. 
In some dry quarries the stone is so soft and porous, so much lighter in colour, and thickly 
interspersed with ova, as to be scarcely distinguished by specimens from the Barnack rag or top 
of the upper Oolite, w hich is equally stored with small turbinated shells. In such cases there is 
but little clay between the two rocks. 
The Forest Marble might thus be considered as a rider to the gieat Oolite rock, and where 
both crop out in the same hills, south of Bath, and thence westward, the former is the well 
defined summit edge of the escarpment. 
Its general course through the Cotswold district may be distinguished by the prevalence of 
timber trees, woods and pasture, and by more numerous sites of population than on the Oolite, 
where water is obtainable only by deep wells, at a great expence. Coarse roofing slates are in 
general use, and flagstones also, in the houses, courts, and streets of the towns and villages in 
the course of this rock. Though its various beds of stone are composed of little else but a mass 
shells > loose whole specimens are rare, and extracted with great difficulty . The organized 
