103 
LOWER BED. 
PONTEFRACT BeST SoIL. 
In Grass. — Rent £3 per Acre. grs. 
Water of Absorption ... 23,500 
Loose Stones 13,125 
Vegetable or Animal 
matters destructible 
by heat ... 16,125 
Fine Sand 4,538 
Lime 12,675 
Magnesia and Iron 21,250 
Alumina 5,912 
Potassa 0,250 
Loss 2,750 
Total 100,000 
Stapleton Soil. 
In Grass. — Rent lOs. per Acre. grs. 
Water of Retention ... 20,250 
Loose Stones 14,500 
Vegetable or Animal 
matters destructible 
by heat 8,812 
Fine Sand 29,385 
Lime 6,000 
Magnesia and Iron 12,250 
Alumina 2,678 
Potassa 0,125 
Loss 6,000 
Total 100,000 
It may be remarked in the first place concerning the rocks, 
that the quantity of clay or rather alumina in them is very 
small ; three by Daniell and three from Tennant, do not con- 
tain one per cent, of that earth. The one from Sherburn, 
and that near Robin Hood's Well, by Holme, are probably 
the upper rock, and contain the one 2.70 and the other 7.75. 
Six of the soils therefore contain under one per cent, and two 
above that quantity of alumina, and to the want of this earth 
must be ascribed partly the small weight of crops which the 
limestone soils comparatively bear. For if we consider that 
the firmness and consistency of a soil is due to the presence of 
this earth, and is of considerable importance in regard to the 
fertility of land, and moreover that the power of condensing 
and absorbing carbonic and ammoniacal gas is also given to 
the soil by alumina, it is easy to perceive the reason why the 
limestone soils require the yearly application of manure to 
each crop, and particularly as they are always friable and 
are at all times freely aerated, which also hastens the decom- 
position of the manures applied to them. 
Upon the inspection of the analyses of the soils, it will be 
seen that the criterion of Liebig, with regard to fertiUty, is 
