208 LOWER OOLITIC ROCKS OF ENGLAND : 
quarries east of Waltham, shoAV about 25 feet of compact earthy 
limestone, coarse-grained oolite, shelly and oolitic limestone. 
These contain a band of yellow micaceous sand or sandstone (1 ft. 
thick) and an occasional band of grey shaly clay.* 
The full thickness of the Lower Estuarine Beds in this locality 
is about 20 feet ; but, at Croxton Kerrial, the thickness proved in 
a well was 12 feet. 
The cuttings on the new railway between Saxby and Bourn, 
showed sections of the Lincolnshire Limestone, which I examined 
in 1 892. South-west of South Witham, there were shallow cuttings 
in compact limestones with scattered oolitic grains and bands of 
coarse-grained and somewhat argillaceous oolite. Here I obtained 
a large specimen of Ammonites u Sowerbyi" Gresslya, &c. The 
beds are much shattered, and occur at a lower horizon than the 
freestone division, which was not exposed along the railway in 
this neighbourhood ; indeed for a mile or more further east the 
cutting traverses only Boulder Clay. Beds of oolite with Corals 
have been worked by the windmill, west of South Witham, and 
freestone was formerly quarried on the eastern side of the village. 
Other quarries may be seen adjoining the railway about 2 miles 
east of South Witham. It is not however until we approach 
Castle Bytham that sections of freestone were exposed in the 
cuttings. 
At Potter's Hill, west of Castle Bytham, the eastern end of the 
cutting showed false-bedded oolitic freestone, overlaid by the 
Upper Estuarine Series, with its layer of ironstone-nodules at the 
base ; and these beds were covered by Boulder Clay. 
Proceeding eastwards to Castle Bytham and thence to near 
Little Bytham, there were fine sections showing, beneath the 
Upper Estuarine clays, the following beds : 
FT. IN. 
f False-bedded oolite, in part very fine- 
grained with coarser and almost piso- 
-.- . i , . litic bands below : the stone stained 
Lincolnshire I pink in places . . . . M 
1 Compact limestone, with scattered oolite 
grains, some layers resembling Stam- 
ford Marble ; seen to depth of 3 
Near the surface the freestone was much broken up, and in 
places there were wide fissures or joints that had been enlarged 
by water-action. At Castle Bytham, where the Upper Estuarine 
Clays had been cleared off the surface of the freestone, it exhibited 
a hummocky appearance, and although the inclined layers of 
false -bedded oolite terminated abruptly beneath the clay covering, 
there was no positive evidence of unconformity, and no traces of 
lithodomous borings were visible. 
The general section at Great and Little Ponton, as described 
by John Morris,f is as follows : 
* Geol. S.W. Lincolnshire, p. 54. 
f Quart. Journ. Geol. Soc., vol. ix. pp. 324, &c. ; Sharp, Ibid,, vol. xxix. p. '265 ; 
Jukes-Browne, Geol. S.W. Lincolnshire, p. 54. ; Brodie, Rep. Brit. Assoc. for 1850, 
sections, p. 76. 
