L {(jli t-Laiul Fa rm iinj. 
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far, however, as mere specific weight or jjravity is concerned, 
these terms are misapplied, and oug-ht sometimes to be altogether 
reversed, for we find that a given bulk of a sandy soil from 
Norfolk, or any other district where such exists, is really heavier 
than an equal bulk of clay taken from the heaviest specimens of 
the weald, gault, or blue lias formations ; but, on the other hand, 
there are some light soils, such as the upper chalk, upper oolite, 
and those composed principally of vegetable matter, as peat or 
bog earth, which have less density than any of the varieties of 
clay mentioned above. The propriety of the common phra- 
seology is therefore the more apparent, as it indicates a general cha- 
racteristic which all light soils possess, viz., looseness of texture, 
and consequently requiring a less amount of force to cultivate 
them than those of a clayey nature. Chemically considered, 
however, there are greater differences of composition among 
light soils than among those which are heavy, for, when resolved 
into their proximate constituents, by the aid of the proper tests 
and solvents, some are found to consist principally of silicious 
or sandy matter (95 per cent, being present in some very 
arenaceous specimens) ; others again are composed principally 
of chalk or carbonate of lime ; and a third class of organic or 
vegetable matter, such as decomposed peat. In the northern 
part of Britain the farmers not unusually employ the terms 
green crop or turnip land in speaking or writing about these soils, 
and these names were at one time quite characteristic of the 
class to which they were applied, inasmuch as turnips could 
only be cultivated successfully upon land of a naturally dry 
and friable nature ; but now the iDoundary line which formerly 
separated green crop fallows from bare fallows is rapidly con- 
tracting on the latter, and, in many cases, turnips are cultivated 
with greater success on well-drained clays than on sandy or 
chalky soils. The generic term light land is therefore gi'eatly 
to be preferred to all others, as it describes correctly the physical 
texture of the soils to which it refers ; for, however much these 
soils may differ from each other in chemical composition, they 
are in a great measure analogous in respect to the mechanical 
or animal force required to dig, plough, or harrow them. 
The arrangement or classification of light soils according to 
their geological derivation is even more difficult tlian that which 
relates to physical texture or chemical constitution, for these soils 
are to be found occupying some portion of almost every forma- 
tion. Thus, for example, the clay soils of England, such as 
those on the red sandstone and plastic clay, are associated with 
tracts or patches of light land interspersed here and there 
throughout them. On the red sandstone the soil is mostly of a 
clayey nature, but there are also portions where the aluminous 
