THE NATURE OF SOIL 39 



is very valuable for the nitrogen which it contains. 

 Advantage is taken of this fact when decaying 

 animal matter is buried to remove the offensive 

 smell, and when sandy loam is used behind cows in 

 the stable. The soil acts much like a charcoal 

 filter which is used to remove objectionable odors 

 from water. 



THE ELECTRICITY OF THE SOIL 



Weak currents of electricity continually pass 

 through the soil and through the plants it nour- 

 ishes. In recent years the effect of soil electricity 

 on plant growth has been studied quite thoroughly. 

 The practical value of passing moderate currents 

 of electricity over and through the soil by means of 

 wires has been demonstrated in several European 

 and American fields. For this specific purpose 

 Messrs. R. &B. Bomford, near Evesham, England, 

 have 19 acres of land with wires suspended 16 feet 

 above the ground so as not to interfere with steam 

 plowing. The current discharged from the wires 

 is generated by a dynamo. This treatment is said 

 to increase the yields of barley and wheat 25 per 

 cent, and give a still larger increase of straw. It 

 makes the plants germinate quicker and grow 

 lustier. The current is turned on morning and 

 evening until harvest. In our own country, several 

 small fields and greenhouse soils have been treated 

 with electricity from wires sunk in the soil, 

 with decidedly beneficial results. The U. S. 

 Department of Agriculture is making a special 

 study of this matter. 



Most of the beneficial effect of electricity is 

 probably due to the fact that it makes some of the 

 plant foods more soluble; perhaps, also, it enables 



