82 ROGK GARDENING FOR AMATEURS 



the nature of the subsoil. Clay may prove unsatisfactory, 

 as water-rats and other creatures sometimes bore through 

 it and cause leakage. 



Masonry ponds are good, and may be built of non- 

 porous stones or of hard non-porous bricks set in cement. 

 Concrete is largely employed, and when properly made 

 and of sufficient thickness is perhaps the most satis- 

 factory. A combination of stones and concrete is often 



A Pool among the Rocks. 



excellent, and may be commended to those who have 

 plenty of odd stones or broken bricks which they may 

 desire to use up. The course we have followed is to 

 put a layer of stones and broken bricks at the bottom, 

 to run concrete among them so that every crevice 

 is filled, and then finish off with concrete and cement to 

 a total thickness of about six inches. 



After deciding what material to employ, and getting 

 it ready, the hole should be excavated. The soil is taken 



