THE SOIL 



85 



This experiment can, if we please, be tried with more 

 tumblers, to the number of six or seven. It is plain, how- 



FIG. 51. THE MAKE-UP OF A SANDY LOAM. 



The first five bottles show different grades of sand. The next two show 

 silt and clay. Such a soil naturally drains well. 



ever, that we shall only separate our grades of earth into 

 classes that will not be of much value to us. We have already 

 found the important parts of loam, 

 in coarse and fine sand, silt, and 

 clay. 



If now different members of a 

 class examine in this way the loam 

 from their gardens, wide differences 

 in them may be found. One may 

 have more sand, another more silt, 

 another more clay. Names have 

 been given to these different earths : 

 sandy loams, medium loams, clay 

 loams. Even without such an ex- 

 amination the loams can roughly 

 be distinguished from each other 

 by their color, for the sandy loam is light brown, the 

 medium a medium brown, and the clay loam a dark brown 

 that at times almost becomes black. 



FIG. 52. THE MAKE-UP OF 

 A CLAY LOAM. 



The left hand bottle. con- 

 tains sand, the next silt, the 

 next clay. Such a soil is 

 naturally moist. 



