ioo THE NEW . ICRICULTURE. 



down into more congenial conditions, they have awakened from 

 ilu-ir sleep of a thousand years and gone to work with all 

 tin- vigor of .young maturity. When their amazing vitality 

 is recognized, it is not so difficult to understand their pro- 

 digious activity when operating under the favorable condi- 

 tions of our Summer months and in our cultivated fields. 



If one were to unearth a buried city, the streets and struct- 

 ures all the surveys and plans, the shops and homes, the 

 storehouses and laboratories would in themselves attract at- 

 tention and challenge study, but their greatest interest would 

 lie in the revelations which they made of the living beings who 

 once walked and worked in them. So also is it with the soil. 

 These parts of it which are not endowed with life attain their 

 highest significance as the home and habitat of a living and 

 myriad population. Upon and between the molecules of mat- 

 ter of which the soil is composed they live and labor and mul- 

 tiply and thrive. They are divided into classes which feed 

 upon different si nces and perform different functions. 

 Individually also the.v differ in size and shape and capacity. 

 They all, these so.i bacteria, require warmth and air, and they 

 are active in darkness but not in light. Some obtain their 

 sustenance from the atmospheric air which is mingled with 

 the particles of the soil ; others from soil moisture, though too 

 much water destroys their activity. Still others feed upon the 

 rootlets to which they themselves furnish food, as slaves might 

 live at the expense of the master whose farm they tilled ; while 

 others still prefer freedom though compelled to obtain their 

 sustenance from the inorganic grit which for food purposes 

 would seem to be as poor in quality as it is abundant in 

 quantity. It is probable, however, that in the last analysis we 

 shall find that all classes of soil bacteria lay the earth, the air 



