94 
TEW: EXTENSION OF MINING OPERATIONS. 
ferous rocks, whose decayed frag-ments mixed with sediment, (and 
together forming- seat earth or "clay") are now manufactured 
into bricks and terra cotta designs. 
These magnificent kihis can turn out 100,000 bricks per week. 
The clay contains in 100 parts : — 
Moisture 
... 4-80 
Organic Matter and combined Water 
... 7-71 
Silicia ... 
... r)3-61 
Protoxide of Iron 
... 0-72 
Peroxide of Iron 
... 3-68 
Lime 
... 2-02 
Magnesia 
... 1-84 
Alumina 
... 25-% 
Alkalies, other substances and loss... 
... 0-GG 
100-00 
In the sample sent, one oi' two small rounded nodules were 
found, which on analysis consisted chieliy of Carbcmate of Iron. 
The Aketon Hall and Featherstone Manor Collieries belonging 
to Mr. Geo. Bradley, situated by the side of the Lancashire and 
Yorkshire Railway are worked ; the " Stanley Main" bed of coal, 
f) feet in thickness, at a depth of 240 yards, and the " Shale 
Seam," o feet thick, at a distance of 220 yards from the surface ; 
the fuel is of superior quality from each mine. 
Additional works for winning the celebrated ''Earnsley Bed," 
which has been proved at a distance of 300 yards from the surface, 
are now nearly completed. This bed, Mr. Bradley says, is found 
to be 12 feet in thickness, and its existence at Featherstone, is, I 
hope conclusive 'testimony that it will be found to the South and 
South-East of Pontefract. 
In the strata intervening between the surface and the Stanley 
Main Coal at these Collieries, salt water is found at a depth of 
about 200 yards, indicating that the salt rock exists somewhere in 
Yorkshire, but where has not been proved.* The recent discover- 
ies near Newcastle-on-Tyne may, probably at no distant day, lead 
* The salt has just been found at Middlesbro'. 
