SOILS AND THEIR COMPOSITION 161 



pause and consider what would have happened naturally. 

 Suppose for argument's sake the cabbage field were left 

 to follow its own sweet will. Putting caterpillars out 

 of the reckoning for the time, we should find most of 

 the heads " bolt " and in due course a cloud of seeds 

 would be borne away on the wings of the wind and by 

 birds and other agencies, large numbers, too, falling on 

 to the soil beneath to carry on future cabbage generations. 

 But, and here comes the vital part, all the old plants 

 would fall and rot into the ground, returning and indeed 

 increasing the organic wealth of the soil from which they 

 sprang. This fact is thoroughly grasped by the Chinese, 

 who are the most successful gardeners on earth, and 

 their system is to return almost daily the plant waste 

 and manure to the soil it was derived from, and as a 

 consequence they are able to support a very numerous 

 population on a relatively small acreage. 



Thus far we have dealt with the vegetable side of the 

 question, but we must now pay some attention to the 

 important services rendered by creatures which dwell 

 in the soil. 



We have already taken a peep into the lives of many 

 insects and other creatiu-es, friendly or otherwise, which 

 frequent the soil. We saw that they were principally 

 beetles, but there were also myriapods, molluscs and the 

 earthworm. We might in addition have included the 

 various tribes of ants which make their homes in the 

 ground underneath the grass and growing crops. Ants 

 as a body perform the useful function of assisting in the 

 aeration of the soil that they are constantly working in, 

 building and re-building the wonderful nests comprising 

 their numerous communities. They are a very interesting 

 study when kept in confinement in thin layers of mould 

 between glass sheets. These enable the observer to 

 witness the ant economy with great ease ; how they wait 

 upon their queen or queens for the all-important process 

 of egg-laying, collecting the latter and sorting the grubs 



