354 
SOILS AND AGRICULTURE OF NORFOLK. 
The peat soils of the Fens are greatly benefitted by 
the application of lime, which breaks up some of the excess 
of organic matter, but the presence of such a caustic sub- 
stance quite possibly renders the potato crop liable to !l scab ” 
disease, and so lime or chalk must be applied cautiously. 
Where the peat is only 4 or 5 feet thick and the Jurassic clay 
is immediately below, trenches are dug across the fields at 
10 yards intervals, and the underlying clay thrown up on 
either side and scattered over the fields. The peat is then 
thrown back into the trenches and the field deeply ploughsd. 
This treatment, by adding clay to the top soil, decreases 
the proportion of organic matter and greatly improves the 
texture and the crop-producing power of the soil. Although 
almost forgotten a few years ago the process is now coming 
back again into favour. It costs about £4 per acre, but 
quickly pays for itself. The labour of digging out the clay is 
extremely arduous, and the operation can only be performed 
in the spring, when labour is needed in other directions. 
Geology. 
With the exception of bands of chalk, gault andl ower green- 
sand running from Hunstanton southward through the 
Brandon area into Cambridgeshire and Suffolk, almost the 
whole of Norfolk is covered with alluvium or drift. The 
rivers of the north and east have cut down to and exposed 
the chalk and crag. The latter is found bordering the rivers 
of the Broads district. The edge of the basin of Jurassic clay, 
in which the Fens lie, only outcrops in a narrow line north 
and south of Downham Market. 
The solid geology of the County is thus exposed in com- 
paratively small patches, and does not give rise to any 
considerable areas of soil, for although H.M. Geological 
Survey maps as chalk the whole of the Breckland, the soils 
covering most of the area are not in any agricultural sense 
chalk soils, but derived from the deposit of blowing sand, 
