6o NATURAL HISTORY 
the black grouait. Several parts of the County have their vegetable 
Soil of this mould, but more efpecially thofe lands which run from 
Padftow on each fide the Alan on the North Sea, to Fawy on the 
South, and thence to St. German’s, from which diftrid the greateft 
part of this County’s com does proceed. The greateft enemy to 
this porous foil is drought ; for loofe as it is, and perpetually dif- 
miffing part of its moifture through its fhelfy foundation, it will 
yield the reft to the fun-beams above, after a long intermiflion of 
rain, by which means both the grafs and com fuffer ; but droughts 
of any continuance are fo rare in Cornwall, that the hufbandmen 
in thofe parts have feldom any reafon to complain. 
sect. iv. The reddilh, Loamy Soil is of clofer texture, confequently retains 
The Loamy, the moifture of rain, the falts it receives from the higher grounds, 
the putrified parts of plants and animals, and the bounty of ma- 
nures, much longer than the Soils above-mentioned : it is not indeed 
fo foon heated and animated (if I may fo fay) by the fun; but as 
the fpring and warm weather advance, it retains the influence of 
of the day, notwithftanding the interpofttion of the night, in fome 
degree, till the day comes on again, and ripens crops much fooner 
than the blacker and loofer Soil. This Soil is moft common on 
level grounds and gentle declivities. 
: Thefe three forts of Soil are not always equally and fpecifically 
diftind from each other, but in different places are fo mixed, 
that the black partakes more or lefs of the red, the red of the 
black, and the flat of either, or both ; neither are they found al- 
ways in feparate peculiar tracts, but oftentimes fo interlaced, that 
one, viz. the higher part of a tenement or barton, fliall be of one 
Soil, and the lower and more champagne of a quite different. 
The attentive hufbandman will eaftly diftinguifh them, and the 
difcreet and induftrious will appropriate to each of them its proper 
culture. To the black and flatty Soils, ftiff, earthy, and calcari- 
ous manure, fuch as may warm, ftrengthen, and confolidate ; but 
to the red and Loamy, every kind of manure that may loofen, 
quicken, and open it. Their management therefore muft be dif- 
ferent, and the product and fertility, c ceteris paribus, will be in 
proportion to the depth of the foil, and as the bottom on which 
that Soil refts contributes to remedy and countered the natural de- 
fers of the Soil above : if the loofe foil has a clofe clay bottom, 
this latter will retain the necefiary moifture ; and if the denfer and 
more compad Soils have a fhelfy, open bottom, this will further its 
fertility by draining off the fuperfluous moifture below. As to the 
reft, circumftances will vary without end, and beyond rule ; and 
where theory cannot reach, experience will decide. 
Dr. 
