112 THE FERTILITY OF THE SOIL [CH. 



are thus mutually interdependent, and any break- 

 down on the part of either causes the collapse of 

 the system. 



Another method of dealing with sandy soils has, 

 however, long been practised. The ease with which 

 they are cultivated and the earliness at which their 

 crops ripen marked them out long ago as eminently 

 suitable for market garden produce. The light loams 

 of East Kent have grown fruit since Tudor times. 

 Vegetables and fruit were long ago gro^vn on the 

 light soils round London, and the practice was ex- 

 tending by the end of the eighteenth century even 

 in places as remote as Suffolk; stable manure was 

 barged from London to Manningtree and sold at lOs. 

 for a five-horse load at the quay, while carrots were 

 grown on the sandy soils and sent back to London. 

 This system has now developed very extensively, 

 and now-a-days considerable areas of sand produce 

 potatoes, vegetables or fruit to be sent off to the 

 cities, and are fertilised with stable manure and 

 other refuse brought back from the cities. 



A third system is in use. The introduction of 

 artificial manures has enabled the sand farmer to 

 be wholly independent either of live stock or of city 

 manures for keeping up the fertility of his soil. The 

 classical instance of tliis type of management is 

 afforded by the Lupitz estate at Altmark, Saxony. 



