397 
any such thickness, I made a tour into the valley of the 
Esk, and found the following strata : — 
ft. in. 
Good Ironstone 0 10 
Dirt 0 4 
Middle bed of Ironstone 1 2 
Inferior Ironstone 0 8 
Bottom bed, good Ironstone 0 7 
Ironstone 3 3 
Yds. 
Strata Ten Yards L0 
Low Bed. 
Ironstone, good 1 0 
Dirt 0 5 
Ironstone, with 7in. course at top 2 6 
Ironstone 3 6 
Solid Ironstone 6 9 
Yielding, per cubic yard, 2J tons, or 24,000 tons per 
acre; the value of the Ironstone then being lis. per ton, 
and the cost of getting being 20d. per ton, which was then 
begun to be carted to Whitby and carried into Durham to 
be smelted. 
The questions then are — What is the geological position 
of this Ironstone mine ? What is the probability of its 
extension ? 
It is evidently in the lias, and below the alum shale, since 
the latter is worked above it. Professor Phillips divides the 
lias into three distinct beds : — 
Yds. 
1. Upper lias shale with alum 66 
2. Ironstone and sandy strata 50 
3. Lower lias shale 166 
282 
Total thickness 282 yards, and the Ironstone is from sixty 
to eighty yards below the alum shale, and therefore about 
f f 2 
