508 LOWER OOLITIC ROCKS OF ENGLAND : 
A spring known as Arthur's "Well, by the road- side north-east of Ivy 
House, Chippenham, yielded 180 gallons an hour, and another spring 
known as Monkton spring by the river side east of the mill, yielded 900 
gallons an hour. 
The well-sinking at the Great Western railway-works at Swindon, 
encoTintered an abundant supply of very saline water at the base of the 
Forest Marble. (See p. 515.) 
At Tetbury the Worwell and Magdalen Mead Springs issue at the 
junction of Forest Marble and Great Oolite north and north-east of the 
town. They uprise in the valley, where the Forest Marble has been 
denuded. Wells in the town sunk through the Forest Marble into the 
Great Oolite, have yielded limited supplies of water at depths of from 
70 to 125 feet. That at Mr. Witchell's Brewery, in Church Street, 105 
feet deep, yielded about 2,000 gallons a day at a depth of 97 feet, but the 
supply at times became exhausted. A bore-hole at Mr. Cook's Brewery, 
125 feet deep, has yielded at the rate of 20,000 gallons a day. 
The deep valleys that border the spur on which the town stands, tend 
to drain the water from the Great Oolite. During wet seasons, the 
valley near the Folly contains a copious brook, but during great part of 
the year the water is conveyed away underground, and this portion of 
the valley is dry. Where the water is sealed up beneath the Forest 
Marble, copious supplies of water have been obtained, as at Weston Birt, 
about 3 miles south-west of Tetbury. 
A boring made at Blind Lane, on the north side of Tetbury, by Mr. 
T. Holloway, of Chippenham, (1892) proved the following strata, which 
I note from specimens kindly forwarded by him. The lithological descrip- 
tions must be considered as general, for single samples in some cases 
represented the strata 70 or 80 feet thick. The details are as follows : 
FT. Ix. 
Marble } Oolitic shell y limestones 
{Pale marly oolitic limestone 
Buff oolite - 
Gritty marl - 
Oolitic shelly limestones 
Oolite - - 
Grey earthy oolitic limestone 
Grey limestones - 
FuUer's [ Grey marl - - 
Eai-th < Grey limestone with Ostrea 
84 feet. I Hard grey marly bed - 
- 8 
- 20 
- 14 
- 6 
- 7 6 
- 84 
- 13 
- 21 
- 8 
- 1 
- 75 
I l nf ^, lor \Hardgrey limestones - - - - 48 
Oolite. J ' J 
300 
Water was tapped in a fissure at 147 feet, and it rose 28 feet (to 119 feet 
from the surface) and there stood : but the quantity was insufficient. At 
300 feet (after the boring had been stopped for a time) pumping was again 
resorted to, and 2,964 gallons per hour were obtained. The pumping 
was continued for a fortnight without lowering the level of the water, which 
remained at 119 feet from the surface. The boring had been tubed to a 
depth of 250 feet, and with perforated tubes from 250 to 270 feet. The 
water then obtained was derived from the Inferior Oolite. 
Near Stroud the yield of water from the Great Oolite is not nearly so 
great as that from the Inferior Oolite ; it being estimated that the springs 
near Chalford yield about 500,000 gallons a day. (See p. 504.) There are 
also springs at Cherington, in the Nailsworth valley. 
The Cerney or Boxwell spring rises (with a temperature of 52) from 
the Great Oolite at South Cerney : the waters d'ive underground in a 
higher part of the valley and issue from a fault where the Forest Marble 
and Great Oolite on the north, are brought against the Oxford Clay on the 
south. The yield here has been estimated at 24 million gallons a day by 
