53 
ley, the limestone is burned and sold for agricultural pur- 
poses. It has the property, when put upon land, of pulver- 
ising strong soils, and, to use a farmer's phrase, of fastening 
or cementing light ones ; the Knottingley bed of limestone 
being held in high estimation by the farmers of the East 
Riding of Yorkshire and Lincolnshire. From the quarries 
at these places, and from South Elmsall, 100,000 tons of lime 
and limestone are annually sent away. 
The limestone in the quarries about Pontefract, and also 
upon the estate of the Right Hon. Lord Houghton, at Glass 
Houghton and at Wheldale, is burnt into lime, and exten- 
sively used for building purposes throughout the kingdom ; 
Wheldale lime being held in great favour by many architects 
for its cementing properties. The commercial value of the 
diflPerent beds of limestone varies considerably, but in the 
neighbourhood of Knottingley from £400 to £600 per acre 
is the marketable price. There is indisputable evidence in 
the fossils Mytylus Squamosus, Terehratida Elongata, Axinus 
TruncatuSy Nautius Frieslebeni, and by chemical analysis, that 
the sea once inundated the area of the country now covered 
by the magnesian limestone formation, and that from some 
unknown cause the waters of the ocean were then decomposed 
in such a way as to permit very generally the precipitation 
of united magnesian and calcareous carbonates. 
The analysis of the lower rock near Stump Cross gives as 
under : — 
Carbonate of Lime 58 '88 
Magnesia 33-96 
Sesqui-oxide of Iron -83 
Alumina (Soluble in Acid) 1*87 
Siliceous Sand (Insoluble Residue) 4'04 
Moisture, &c '42 
100 00 
But the lower Permian Red Sandstone of Sedgwick and 
Smith, which forms W. a fringe to the magnesian limestone, 
