MARCH 177 



In the bottom of a flower-pot jiut a few pieces of broken 

 crockery for drainage, then fill the pot to within an inch 

 of the top with good light earth. In transplanting, be 

 particularly careful not to injure the roots. 



SOIL 



The greater portion of the United States has a soil 

 made by the disintegration of rocks. The sandstones 

 and shales give rise to a red or white soil, which is plainly 

 seen to be due to the adjacent rocks ; Avhile particles of 

 shining mica show the relationship of that soil to the 

 surrounding gneiss, mica schist, or granite. 



In addition to mica, it is very easy to separate out the 

 other ingredients common to granite and other soil, viz., 

 clay, coarse and fine sand, and decayed vegetable matter. 



The decay of the mother rock may have been caused 

 in various ways. The surest and commonest way in 

 which a rock is destroyed is by the freezing of water 

 which has soaked into it, and which in the freezing 

 expands, forcing off small fragments. 



In desert regions where the difference between the 

 day and night temperatures is enormous, travellers often 

 hear the rocks crack, and even see the chips fly, in 

 consequence of the inability of the rock to adapt itself 

 to the rapid contraction and expansion whiich result from 

 sudden changes of temperature, even when no ice is 

 formed. This same cause results in rock disintegration 

 in all parts of the world. 



Still another cause of the decay of rocks and conse- 

 quent production of soil is shown by the yellow stain 

 so commonly seen, Avhich means merely that the iron is 

 oxidizing, or changing to iron rust. In the case of gneiss 

 and mica schist, this oxidizing of the iron results in 



