G#IEAT OOLITE SERIES: NEWPORT PAGNELL. 393 
FT. IN. 
Bluish-grey clay with "race" and 
decomposed pyrites, and much 
ferruginous matter at base - 6 
I Irregular earthy band, with Ostrea 1 6 
Massive bed of banded earthy lime- 
stone - - - - 5 
Layer df selenite. 
Marly limestones with Oetrea Sowerbyi 
and Modiola giUbosa ; much selenite 3 
Seam of selenite. 
Great Oolite 
Limestone. 
Pale earthy oolitic limestone -12 
Layer of selenite. 
Pale earthy oolitic and shelly lime- 
stone - - - 1 
Seam of clay. 
Marly bed crowded with Ottrea 2 
False-bedded shelly oolitic limestone, 
with veins of selenite ; seen to depth 
of 40 
This section may be compared with that seen at Stow-nine- 
Churches (p. 398). The occurrence of so much selenite is a 
remarkable feature ; it is, however, local, and the layers are but 
an inch or two thick. On the whole it seems most probable that 
the selenite l\as arisen from decomposition of pyritic layers in the 
beds above, and the consequent formation of sulphate of lime 
which was deposited along the open planes of bedding and in 
crevices of the fractured rock. 
Newport Pagnell to Olney and Bedford. 
The Great Oolite limestone is quarried to the north of Gayhurst.* 
The beds that have been worked, comprise nearly 12 feet of 
limestones separated by marls. The stone-layers are much 
jointed and fissured, and the walls of the fissures are seen to be 
water-worn. The layers are slightly wedge-bedded in places, and 
some are seen to be current-bedded on a small scale. There are 
hard bands of bluish-grey oolitic limestone, resembling beds of 
Forest Marble, and there are softer layers of marly limestone. 
The former are employed for walling, and the latter for ordinary 
building-purposes. The stone, according to the quarryman, 
requires to "lie out" about 12 months before it is used; it must 
at any rate be well seasoned, otherwise it shatters with the frost. 
Some of the hard layers of oolitic limestone contain marly patches 
and small pebbles of marl, that are suggestive of contemporaneous 
erosion. The fissured and shattered nature of the stone-beds, 
shows that the strata might hold a good deal of water under 
favourable circumstances. 
Further northwards of Stoke Goldington, a brickyard has been 
excavated in dark grey and purplish clays. In company with 
Mr. Cameron, I visited this pit and also a number of exposures in 
the clay (formerly mapped as Upper Lias) along the borders of 
the Ouse valley by Weston Underwood to Olney. We found 
* See foot-note, p. 379. 
