122 ROCK GARDENS 



filled, and on top another course of stones, and 

 so on till the desired height is reached. 



Where a dry wall, which is also to act as 

 a dividing wall, is required, it must be built 

 hollow in the centre, to allow for the soil 

 which is needed for the plants 



Both sides of the wall should slope back 

 from the foot at an angle of 80 degrees, and 

 there should be at least a foot of soil in the 

 centre. A wall of say 6 feet high and 2 feet 

 thick at the top would require a base of 4 feet 

 6 inches wide, allowing for the stones being 

 about 12 inches long (fig. 6). This wall 



