26 BL. Thompson—Clay Beds by the Ouse. 
The top of the Lias Clay at Stoke Goldington is at about 188 feet 
above O.D.,' and this is certainly very near to the level of the top 
of the Lias Clay at two other sections to the eastward, within a mile 
or so, where river gravel is worked to a depth of 191 feet O.D., 
showing that in this particular area the top surface of the clay is 
determined by (comparatively) recent diluvial action, and that higher 
beds may be reasonably expected to occur near at hand where diluvial 
action has not been operative. 
In the absence of exposures of rock at a higher level at Stoke 
Goldington the problem was treated in this way:—Going to the 
N.N.W., we find the base of the Great Oolite limestone at Piddington 
to be at about 300 feet O.D. At a point on the road between Horton 
and Stoke Goldington, about 233 miles from Piddington in a straight 
line, the probable base of the Great Oolite limestone is 260 feet O.D. 
A fall of 40 feet in the distance named means an average dip of 
14 feet per mile along the line indicated; consequently at Stoke 
Goldington, 44; miles from Piddington, there should be a drop of 
55 feet, making the natural base of the Great Oolite limestone there 
245 feet O.D. 
Again, at Ravenstone the base of the Great Oolite limestone 
appears to be about 250 feet O.D. (an investigation of several wells 
indicated this figure), and as the middle part of this village, where 
the Great Oolite source of water gives place to a gravel source, is 344 
miles from Piddington in a direct line, this also gives a dip of close to 
14 feet per mile. Furthermore, at a point about 2 mile south of — 
Ravenstone, towards Ravenstone Mill, Great Oolite limestone may be 
seen in an old quarry as low as about 240 feet O.D., which comes to 
nearly the same figure, viz., 14 feet per mile dip in a southerly 
direction. ‘This last section is about one mile from Stoke Goldington 
brickyard, and as they are N.E. and §.W. of each other respectively, 
and the dip is distinctly greater south-eastward than southward, it 
appears highly probable that the former estimate for the natural 
position of the base of the Great Oolite limestone at Stoke Goldington 
is about correct, viz. 245 feet O.D. ‘This naturally leaves 245—188 
= 57 feet to be filled up; the only question is what with ? 
As there is no recognisable Northampton Sand, either ironstone or 
Lower Estuarine sands, in the area under review, the disposition of 
the 57 feet is left with the Upper Estuarine beds and the upper beds 
of the Upper Lias. 
Near to Olney, half a mile north of the railway station, and a little 
over 4 miles north-east of Stoke Goldington, a well was sunk through 
27 feet of Upper Estuarine beds,” and as this is a very good thickness 
for the beds in question, and yet not greatly different from the 
thickness of the same beds at Roade cutting (24 feet 10 inches), 
a little over 6 miles to the north-west of Stoke, we may fairly well 
accept it as the local thickness, and if we do it leaves 30 feet to be 
made up with Upper Lias at Stoke Goldington. 
1 All levels were taken with a Watkin aneroid barometer on a moderately satisfactory 
day for such work, but of course require revision for strict accuracy. 
* H. B. Woodward: ‘‘ Jurassic Rocks of Britain,’’ vol. iv, p. 394. 
