130 NECESSITY OF PULVERIZATION. 



cliange, therefore, by which is produced a crumbling 

 consistence of the soil, not however through sub- 

 division, but rather by binding, is doubtless to be 

 ascribed to the strong net-work of fine root-fibers, 

 which can develop, spread, and ramify much more 

 in the loose than in heavy and close soils." 



The importance of pulverization appears from these 

 considerations. 



1. The stifi"ness of clay soils prevents the drains 

 from accomplishing the work for which they were 

 intended. 



2. Silicious and gravelly soils are unproductive, 

 because they do not retain the heat, gases, and 

 moisture, as they would if properly pulverized. 



3. Heavy earths are cold if not pulverized. They 

 cannot absorb heat from the atmosphere, because it 

 does not penetrate them ; and they do not receive 

 it from the decomposition of manurial substances, 

 as such a process is arrested by the absence of the 

 oxygen of the air, and the presence of stagnant 

 water. The fact that air fills pulverized and culti- 

 vated land, can be proved by plunging a pot of 

 earth under water, when bubbles will rise contain- 

 ing the air which was forced out when the water 

 ran in. 



The editor of that excellent periodical, " The 

 Gardeners' Chronicle," thus beautifully illustrates 

 the influence of " underground climate " : " The 



