293 
Variations of the Four-course System. 
time was spent in filling-in cropping schedules to be attached 
to leases. Every field on the farm was numbered and named, 
and the crop for each year during the whole period of a 
nineteen yeai’s’ lease was entered in tabular form. Compliance 
Avith the schedule was provided under the usual pains and 
penalties, and could not be deviated from except by a Avritten 
authority from the agent. 
Marvellous progress has, howev'er, been made during the last 
forty years, within Avhich period the pi’actical man has acquired 
a better knowledge of the raAV material to which his energies are 
directed. An acquaintance Avith the mechanical nature and 
chemical properties of the soil enables the intelligent cultivator to 
successfully stimulate and bring into profitable activity its latent 
capabilities. Soils may for our purpose be fairly grouped under 
five separate heads : — 
1. Sandy soils, containing 75 per cent, and upwards of 
siliceous matter. Some of these soils, though originally barren, 
have been reclaimed from sterility — often, it must be admitted, 
at great cost— by the application of clay and by other means, 
and by the extended groAvth of forage crops. These crops were 
at the outset ploughed in with the object of increasing the 
humus in the soil, and subsequently trefoil, mustard, rape, and 
other succulent crops wei'e eaten on the land by sheep ; by such 
means the soil was consolidated and improved. Many of the 
sandy soils ai’e now capable, under skilful management, of pro- 
ducing good crops of roots and spring corn, and these soils have 
long been cultivated under the four-course system. 
2. Soils rich in A'egetable matter, or humus, conlainiug 
more than 10 per cent, of organic matter. Soils of this class 
were originally for the most part Avater-logged, and were fre- 
quently clothed with rushes and sedges. Where such soils 
contain 15 or 20 per cent, of clay, thorough drainage and sub- 
sequent appropriate treatment Avill convert them into productive 
tillage land or good permanent pasture, as may be desired. On 
such soils the potato crop luxuriates, and formerly the soils of 
this class were worked on the four-course system. 
3. Marl soils, containing about 10 per cent, of carbonate of 
lime and 20 per cent, of clay. Many of the Chalk soils and 
the friable soils of other limestone formations belong to this 
class. Under skilful management these soils seldom fail to pro- 
duce good crops, and are knoAAni as healthy stock breeding and 
feeding land. 
4. Loamy soils, containing from 40 to 70 per cent, of clay. 
These constitute the most valuable class of soils in the country. 
