CHAPTER III 



WHAT LIMB DOES TO CLAY 



Apparatus required. 



Clay J about 6 lbs. Some of the clay from Chapter II 

 may^ if necessary^ he used over again, lAme, about J Ih, 

 SixfunnelSj stands and disks [2]. Twelve glass jars [2]. 

 Lime water \ 



If you are in a clay country in autumn or early winter 

 you will find some of the fields dotted with white heaps 

 of chalk or lime, and you will be told that these things 

 "improve" the soil. We will make a few experiments 

 to find out what lime does to clay. Put some clay on to 

 a perforated tin disk in a funnel just as you did on p. 14, 

 press it down so that no water can pass through. Then 

 sprinkle on to the clay some powdered lime and add 

 rain water. Soon the water begins to leak through, 

 though it could not do so before ; the addition of the 

 lime, therefore, has altered the clay. If you added lime 

 to a garden or a field on which water lay about for a 

 long time in winter you would expect the water to drain 

 away, especially if you made drains or cut some trenches 

 along which the water could pass. There are large areas 

 in England where this has been done with very great 

 advantage. 



^ Lime water is made by shaking up lime and water. It should be 

 kept in a well-corked bottle. 



2—8 



