478 LOWER OOLTTIC ROCKS OP ENGLAND : 
Great Oolite. 
The Bath Stone is quarried and mined over an extensive area between 
Bradford-on-Avon and Covsham. Some of the underground tunnels on 
Corsham Down are said to extend for several miles, and they are con- 
nected with the surface by an incline up which the stone is taken along a 
tram-line. The open works date from a very early period ; and some of 
the deeper works date from the time when the Box tunnel was con- 
structed (about 1845). There is from 6 to about 25 feet of freestone, and 
the layers are from 1 to 6 feet thick. (See p. 261.) 
At Bradford-on-Avon, the best freestone is about 6 feet thick : and it is 
worked underground. The stone above it is cleared off for about 8 inches 
or 1 foot, and then the rock is sawed oat in huge blocks of from two to 
five tons in weight. The average size of the blocks is about 40 cubic feet, 
but sometimes blocks of 70 or even 90 cubic feet (5 tons) are obtained. 
It is a good weather-stone, and is obtained not only at Bradford, but at 
Upper Westwoocl and Avoncliff (Ancliff). (See p. 261.) At Winsley a 
good weather-stone is obtained ; the best bed, known as Winsley Ground, 
is from 3 to 4 feet thick. At Limpley Stoke, the best freestone is about 
6 feet thick ; it is known as Stoke Ground, and is a good weather- 
stone. 
On Odd Down and Combe Down,* near Bath, there are extensive 
quarries where 10 or 12 feet of freestone is worked. The stone contains 
thin and impersistent veins of spar, and iron-stains, which do not how- 
ever affect its durability. I was informed by Mr. Love that the stone, 
although more or less fissured, does not deteriorate when near the 
surface ; that, at Odd Do%vn, which in places is covered only by a foot or 
two of rubble, being sound and durable, while the Farleigh Down Stone 
of Monkton Farley (or Farleigh) obtained beneath clays, is not reckoned 
so good a weather-stone. The best stone is about 4 feet 6 in. thick ; but 
very large blocks are not to be had. (See p. 265.) Larger blocks can of 
course be obtained where the stone is mined, and it is free from the 
disturbing influence of the weather. 
The stone is quarried and mined in several places at Box, the details 
varying in different places. (See p. 267.) 
The Box Scallett Stone, said to be excellent for carving, is not now much 
worked, probably on account of the expense. The main freestone 12 to 
14 feet) occurs lower down, and this can be mined beneath the hard rags, 
which constitute a Eoof Bed. One of these rags known as the "White Eag 
is an oolite that "dries as white as snow." Very similar beds occur 
between Tetbury and Kemble, and near Minchinhampton. 
The Box freestone or' Ground bed forms a good weather-stone, it 
whitens on exposure. Blocks weighing 6 tons are sometimes obtained ; 
about 14 cubic feet of stone weighing one ton. The stone is often so 
broken up that much refuse has to be extracted. The good stone is from 
9 inches to 3 or 4 feet in thickness : it is said to be a better weather-stone 
than that at Bradford, but is not usually obtained in such large blocks. 
The Eag bed is so hard that the freestone is seldom worked beneath it in 
open quarries. Overlying the Eag bed, there is a freestone, known as 
the Corngrit ; the best beds attain a thickness of 4 feet. The rock is a 
somewhat earthy and shelly oolite, suitable for inside work. 
The Corsham Bath-stone, which is mined on Corsham Down and Eidge 
and at Monks Park to the south, comprises from 15 to 25 feet of free- 
stone in several beds. These are worked underground, to a depth 
sometimes of 100 feet. The best beds, known as Oorsham Down and 
Monks Park stones, are about 4 feet thick. The stone is a fine uniform 
oolite, with few fossils. Blocks about 100 cubic feet, and weighing 
about 7 tons, are sometimes brought up : as a rule about 16 cubic 
feet of stone go to the ton. The blocks are stacked in summer ; being 
raised above the ground, to dry; and they are ready for use in the 
* For Analysis, see Mem. Geol. Survey, vol. ii,. Part 2, p. 690 ; also Builder 
vol. lix. p. 324 (1890). 
