VOL. XVL.(1) WATER-SUPPLY AT LEIGHTERTON 39 
a few masses of limestone occur in the clay, and this being 
so, it would appear that the deposit as a whole resembles 
the basement-beds of the Forest-Marble Series, proved 
during the construction of the South Wales Direct Line, 
in the hills east of Old Sodbury. There the basal beds 
comprised “shales and clays containing two thick lime- 
stone-beds.” 
I think that the clays which hold up the water at 
Leighterton must be paralleled with the celebrated 
Bradford Clay, which at Bradford-on-Avon constitutes 
the basal deposit of the Forest-Marble Beds. There is a 
very instructive section at Tiltup’s End, on the Bath Road, 
about a mile-and-a-half south of Nailsworth, which shows 
the junction of the Forest-Marble Beds with the Great 
Oolite proper. An excavation at Leighterton, made in a 
suitable place, would most likely reveal a similar sequence 
of deposits. 
QUARRY AT TILTUP’S END, NEAR PAINSWICK 
Thickness tn 
feet inches 
1. Limestone, whitish, oolitic, in thin flaggy pieces 
at the southern’ end, but yellower, more 
crystalline, and much ‘harder at the northern 
end ; Ostrea Sowerbyi, Lycett, Limea EN 
(Sowerby), Beet: : 4 a 
. Marl, yellowish, oolitic, with thin seams of clay 
crowded with Rhynchonella obsoleta (Sowerby), 
Ostrea Sowerbyt, Lycett, and O. acuminata, 
Sowerby; but along the southern face of the 
quarry this deposit is represented by an oolitic 
marl, barely an inch thick, and devoid of 
specimens of the Rhynchonella, 4” to 6” she O 
3. Limestones, brown, oolitic, shelly, more massive 
than bed 1, but obliquely laminated. They are 
coarsest and most shelly where the oblique 
lamination is most pronounced. Few recog- 
nizable shells, except Ostrea Sowerbyz, Lycett, 
seen ae ee ee ee wae ee 8 O 
The soil is very argillaceous, and of a rich reddish- 
brown colour. No doubt clay is the next deposit above 
FOREST MARBLE 
nN 
ou 
GREAT OOLITE 
