THE 
37 SOIL 
sprouting and developing. You willunderstand 
why such soil is not often in the market. It is 
Nature’s materials plus man’s intelligent labor; 
and he who has it, is usually found working 
it to his own profit. 
Some soils are easily put into condition: others 
require much time and labor, but all always 
repay. It is well, however, to avoid a hard, 
cold, clayey soil if possible; it takes so long to 
warm up, that the seeds make little progress. 
Of course, steady persistent effort will greatly 
improve even this soil, and if that is the sort 
you have, you must do your best with it, but 
the average gardener cannot afford to wait. 
Compared with agriculture, which has been 
known in some form ever since there have been 
any records, tillage is very new. Like many 
another important thing, it was discovered 
quite accidentally by an English farmer, named 
Jethro Tull. He found that by stirring up 
the soil about his plants, he got better returns; 
and gave his discovery to the world. But he 
could not explain why it was so; he merely 
knew the fact itself. Science has since dis- 
covered that it is due to the action of the air 
in helping to break up the many compounds 
found in the earth containing plant food. It 
was a simple thing, yet it has really revolution- 
