21 



their carpet of dead foliage, by the winds or by the 

 hand of man. 



" The fallen leaves/' says Liebig, " contain such 

 trilling quantities of potash and phosphoric acid, in 

 comparison to their mass, that it is difficult to account 

 for the injurious consequences arising from the raking 

 up and ivinoval of the fallen leaves in woods." 



It is difficult only when we lorget the conditions 

 existing in the woods. There the protection of the 

 soil, the perpetual moisture, and the carbonic acid 

 constantly forming, work without ceasing beneath 

 the mulch, crumbling and moldering the minerals 

 into an impalpable and soluble state, eady to be 

 absorbed by plants or trees. 



Liebig admits that " the injury is, perhaps, rather 

 attributable to the fact that the remains of leaves 

 and plants constitute a lasting source of carbonic 

 acid, which carried by the rain to the deeper layers, 

 must powerfully contribute to disintegrate and decom- 

 pose the earthy particles." 



These substantial truths should establish the ad- 

 vantage, if not the necessity, of shelter and moisture 

 to improve the soil, and also to promote the growth 

 of our crops. 



Yet there is no scarcity of water in our favored 

 country. 



We have a rainfall of 4,000 tons per acre every 

 year. But what becomes of it ? 



Professor Johnson says : ' According to the ob- 

 servations of Dickinson at Abbot's Hill, Hertfordshire, 

 England, and continued through eight years, 90 per 

 <Mit of tbe water falling between April 1st and 

 October 1st evaporates from the surface cf the soil, 



