78 ROCK GARDENS 



simplest method of accomplishing this is, with 

 the help of the rocks, to make the banks into 

 a series of terraces ; at the same time the rock- 

 work should follow the same line or dip of the 

 strata throughout. 



These terraces should vary in every con- 

 ceivable manner : height, width, outline, and 

 gradient. This last is important, for if it is too 

 steep the moisture will run off too quickly and 

 not percolate the soil, and if it is too flat the 

 ground is apt to get sodden. A fair gradient, 

 such as 6 inches in 2 feet, is about right. It 

 will also be necessary during the construction 

 to make a number of pockets or compartments 

 in order to give a variety of aspects, the 

 advantage of which will be fully appreciated 

 when the time for planting comes. 



In order to avoid getting the terraces in 

 regular planes, let them, in places, merge into 

 each other ; perhaps where they join a fresh 

 one may be started on yet another level. 



In the long and gentle gradients the terraces 

 will naturally be wider and not so deep, very 

 different from the formation in the bolder and 

 steeper parts, where each rock almost touches 



