48 



SCHOOL COURSES. 



are likely to travel.* Keep for use at other times sealed 

 samples of the stream in different conditions. 



Note the formation of alluvial plains, if such occur in 

 your district. 



Study and make sketches of river bends, noting how 

 islands are sometimes formed (Fig. 3). 



Action of sea eating away of cliffs, blown sand, and 

 action of sand-binding grasses illustrate changes on the 

 sea- shore. 



Fact to be grasped by pupils : Denudation is a reality. 



It has gone on for innumerable ages : appeal to sedi- 

 mentary rocks which by elevation may have become exposed 

 to view. 



(fc) Simple Analyses : 



1. Separation of the Or- 

 ganic and Inorganic Con- - 

 stituents. 



2. Separation of the Solu 

 ble and Insoluble Constitu- 

 ents. 



Take a small quantity of 

 garden soil, dry, weigh, in- 

 cinerate till all blackness and 

 smoking is gone, cool and 

 weigh again. Loss of weight 

 k = organic constituent. 



Take a fair quantity of soil. 

 Soak it with 1 per cent, solu- 

 tion of Citric Acid, whose 

 action may be regarded as 

 equivalent to that of the root- 

 let sap upon the soil. Filter 

 k and evaporate the filtrate. 



The filtrate contains the readily soluble mineral matter 

 which may be regarded as available for plants. 



* The results obtained in this way are only roughly approximate, 

 since we are assuming the rate of deposit in still water to be the 

 same as that in runinng water. But our main point is to emphasise 

 the/actf of transport. 



