100 THE FERTILITY OF THE SOIL [CH. 



growth of clover and producing a more nutritious 

 herbage. 



Trouble still arises from the presence of epizootic 

 diseases in animals grazing on clay land, but this will 

 no doubt be overcome as fuller knowledge is gained 

 of the fauna of the soil. Often, however, the drainage 

 is faulty. Over much of the Midland clay area the 

 drains were laid in the middle of the last century 

 at a depth of 4 ft; this is now known to have 

 been too far down. Here the trouble arises from the 

 slowness with which the rain water gets away. The 

 drains should, therefore, only be placed about 2 feet 

 deep. In many cases also the grassland needs plough- 

 ing up and resowing with a suitable mixture. Finally, 

 many clay farms need a good dressing of lime or 

 chalk over the whole land, arable and grass alike. 



Once the grassland is improved it commonly gets 

 well treated ; manure is put on if it is cut for hay, and 

 concentrated food is supplied to the animals put out 

 to graze on it The grassland is consequently main- 

 taining or increasing its fertility. At the present 

 time, therefore, clays within reach of cities have dis- 

 tinct possibilities. Those further off, however, are 

 frequently in a poor state and are more famous for 

 the fox-hunting they afford than for their agriculture. 

 Sometimes summer milk is produced to be sold to 

 the cheese makers, but this trade is at a standstill in 

 winter ; sometimes also young store stock are raised 



