116 THE MAGAZi'nE OF HORTICULTURE. 



extensively ramified, and sooner find the rich loam and ma- 

 nure intermingled deeply with the soil. The leaching pro- 

 cess, as it is called, is reversed, and takes place upwards more 

 than at any other time, or, in more scientific phrase, capillary 

 attraction is increased. As each particle of moisture is evap- 

 orated from the surface, it is succeeded by another, and the 

 whole soil is filled with the ascending moisture and gases, 

 which are appropriated by the numerous rootlets as they have 

 need. 



The wet season is also a blessing to the deep cultivator. 

 The more rain, the more heat, ammonia, carbonic acid, and 

 other organic elements are left in the soil as it descends. As 

 each drop filters through, it is succeeded by another, or by 

 air, both essential to vegetation ; and to dissolve, act on, or 

 combine with, the inorganic elements of the soil. As the 

 water drains off, air is sure to follow, and this is the proper 

 mode of its circulation. Each is also generally at a higher 

 temperature than the undrained land, and the warmth of the 

 under soil is therefore relatively increased. The farmer often 

 objects to this waste of water, and would fain retain it for a 

 dry time ! The trenched and porous soil holds water like a 

 sponge, notwithstanding the drainage. It retains or can com- 

 mand enough for the wants of vegetation. But let us see the 

 operation on the undrained land. 



The farmer often speaks of his "cold wet land." No va- 

 riety of soil, in any location, is, of itself, colder than another. 

 The very water which trenching, draining, &c,, allow to pass 

 off after imparting its virtues to the soil, if retained on or 

 near the surface by hard impervious subsoil, becomes itself, 

 by its changes, the source of the coldness complained of. 

 Instead of running off, it evaporates, and by this process ab- 

 • stracts a great quantity of heat from the soil and surrounding 

 atmosphere. The evaporation of a pound of water requires 

 about 1000° of heat ; some authors stating it less and others 

 more. Or it reduces 100 pounds of air 45°. This is revers- 

 ing the experiment of Prof. Johnson, in Espy's " Book of 

 Storms,^^ where he says, " a pound of vapor" condensed to 

 water "would heat 100 pounds of air about 45°." The 



