398 
200 yards from the bottom of the lias, or from the new red 
sandstone, which is an excellent guide to its discovery, 
The next question — Is this valuable Ironstone co-extensive 
with the lias ? and can we expect to find it about the middle 
or near the bottom of the lias in its whole extent through 
England ? The lias extends from the Tees to Lyme Regis, 
in Dorsetshire. But even before reaching the Humber 
the whole of the Oolite beds of the North Riding have 
become so much reduced in thickness and altered in 
character, as to be with difficulty identified. In the printed 
reports of the Society, of August, 1841, there is a long 
paper drawn up by Sir J. Johnson, Mr. Ledgard, and my- 
self, and read at Hull, with a minute account of the Geology 
and Agriculture of the Oolite in the wold district of York- 
shire, in the neighbourhood of North and South Cave; where 
the whole thickness is reduced to only sixty yards, while in 
the North Riding it is at least 700 yards. 
Yds. 
The lias from Pocklington to the Humber ... 25 
In the valley of the Esk 282 
No Ironstone of this value exists under the Wolds, since in 
this survey, the Rev. W. Harcourt, Sir J. Johnson, Mr. 
Ledgard, Captain Shaw, of Brantingham, and myself, were pre- 
sent, and I do not think we should have overlooked it. There 
is, however, no doubt about a similar Ironstone, and even a 
richer mine, being found about four miles south of Middles- 
bro'-on-the-Tees, under the Stapylton estates, and at Eston 
Hall it is 14 feet thick of clear Ironstone. Professor Phillips 
and Mr. Holt, before the Commissioners of Lunacy, deposed 
that in the Stapylton estates alone there are three millions 
of tons. This Ironstone is exceedingly rich in iron, containing 
45 per cent, of iron, while none of our Yorkshire Ironstones 
in the coal district contain more than 33 per cent.* The 
* Costs getting, Is. 3d. to Is. 6d. per ton. 
