388 



NATURE STUDY AND LIFE 



blackboard in the following form. If desired, the children 

 may copy them into their notebooks. 



With No. 5, keep the top, to a depth of about half an 

 inch, loose and fine by stirring.^ 



The influences of trees on weather and climate are topics 



1 These observations may be repeated in various ways tliat will readily 

 suggest themselves to the teacher. The two main facts that the children 

 should get, are, first, that loam and leaf mould protect the water in the 

 soil from drying up; and, second, that a covering of fine dry dust serves 

 this purpose most effectually. They should thus learn, as Professor Bailey 

 puts it, how to water their gardens with a rake instead of with a watering 

 pot. It would also be well, in clayey districts, to have a third tumbler of 

 loam and stir it thoroughly, after adding the water, to show the effect of 

 working the soil while wet ; it will then dry in hard lumps. 



In this connection, too, it is well to repeat the common experiment of 

 wetting two spots on the blackboard and fanning one to show how much 

 more rapidly it dries. The trees thus prevent the winds from drying out 

 the water in the soil. 



Shade is another important influence that trees exert. If possible, to 

 the above eight add three tumblers filled respectively with gravel, sand, and 

 loam and set in the sunniest window of the schoolroom. This will demon- 

 strate, aside from the influence of forests, the value of planting gardens so 

 that the ground may be well shaded in districts where drought is common. 



