20-i <( 1/riv.vno.x. 



soil, and, if it be a bulb, tuber, or tap, to assume 

 the form requisite for its largest development. 



It must be evident that roots, penetrating the soil 

 to a depth of two feet, anchor the plant with greater 

 stability than those which are spread more thinly 

 near the surface. 



The roots of plants traversing the soil to such 

 great distances, and being located in nearly every 

 part, absorb mineral and other food, in solution in 

 water, only through the spongioles at the if < /"/.>-. 

 Consequently, by having these ends in every part of 

 the soil, it is all brought under contribution, and the 

 amount supplied is greater, while the demand on any 

 particular part may be less than when the whole re- 

 quirements of plants have to be supplied from a depth 

 of a few inches. 



The ability of roots to assume a natural shape in 

 the soil, and grow to their largest size, must depend 

 on the condition of the soil. If it is finely pulverized 

 to the whole depth to which they ought to go, they 

 will be fully developed ; while, if the soil be too hard 

 for penetration, they will be deformed or small. Thus 

 a parsnip may grow to the length of two and a half 

 feet, and be of perfect shape, while, if it meet in its 

 course, at a depth of eight or ten inches, a col'l, hard 

 sub-soil, its growth must be arrested, or its form in- 

 jured. 



Hoots are turned aside by a hard or wet sub-soil, 

 as they would be if received by the surface of a plate 

 of gla->. 



Add to this the fact that cold, impenetrable sub- 



