Farming of Cornwall. 
419 
corn crops average 36 bushels of wheat, and from 48 to 60 bushels 
of barley ; on the ordinary land 20 bushels of wheat, 34 bushels 
of barley, and 45 bushels of oats, per acre. There are only a 
few flocks of sheep kept ; the fanners purchasing the ewes in 
lamb in the autumn, and selling them fat the following spring 
and summer. 
29. The next district, usually called the Meneacje, will finish 
our survey of the county. It comprehends 58 square miles, 
25 miles of which are occupied by the serpentine formation, 25 by 
the slates, and the remainder is divided by diallage, hornblende, 
and greenstone-rocks. The southern portion of this district is 
known by the name of the Lizard Point, and forms at the same 
time the most southern promontory of Britain. 
Serpentine. — The greater part of this formation offers a most 
marked example of barrenness : it is a flat table-land, retaining 
the water on its surface in every direction. It is characterized 
by producing a most beautiful heath — the " erica vagans." Its 
unproductiveness is generally attributed to the large per centage 
of magnesia which it contains, forming with silica a silicate of 
magnesia, and having little or no lime or alumina entering into 
its composition.* It occasionally happens that veins of diallage 
and hornblende run through the serpentine, which intermixture 
adds considerably to its fertility : where this occurs, the land is 
rented from 18s. to 245. per acre; but the general character in 
other respects is barren and unfruitful. The system adopted to 
cultivate the soil, in lieu of draining, is to plough deep water- 
furrows along and across the fields. Nothing, however, but tho- 
rough draining would avail here. The cropping is wheat, bar- 
ley or oats, and seeds, with one or two per cent, of potatoes 
preceding the wheat crop. The wheat averages from 12 to 16 
bushels, barley from 17 to 24 bushels, and oats from 28 to 36 
bushels per acre. 
30. Hornblende. — The contrast between this soil and the ser- 
pentine, which it adjoins, is the exact difference between an ex- 
tremely fertile and a very indifferent one. Its surface is beau- 
tifully undulated, presenting a remarkable contrast to the flat, 
monotonous aspect of the serpentine (see section). Land on this 
* Analysis of the Serpentine Rock. 
Magnesia .... 
36 
G8 
40 
G4 
Silica .... 
42 
50 
41 
95 
Alumina .... 
1 
00 
0 
37 
Lime .... 
0- 
25 
0 
00 
Oxide of Iron 
1 
50 
2 
12 
Oxide of Manganese . 
0 
62 
0 
00 
Oxide of Chrome 
0 
25 
0 
00 
Water .... 
15 
20 
11 
C8 
Carbonic Acid and Bitumen 
0 
00 
3 
42 
