COMPONENT PARTS OF A GARDEN 189 



his mind the sort of rock in which his work is to 

 be developed. If in limestone, the ledges will be 

 deep and bluffs bold ; if sandstone, the ledges will 

 be more broken. Also he must not waver in his 

 intention as to the dip of the strata. Should he 

 wish to make effects with prominent bluffs the 

 general dip throughout should be backward to- 

 wards the " mainland/' for only under such cir- 

 cumstances are bluffs naturally formed. It is not 

 at all the same thing to secure stability for the 

 bluff itself by giving a backward dip, for it will 

 merely appear a mass distinct from the neighbouring 

 ledges. Moreover the designer should know what 

 he means to plant : here is a sunny ledge for 

 gentiana acaulis; there is a northern aspect for 

 ramondia pyrenaica ; here is a part slightly over- 

 hung for androsace ; there a steep prominence to 

 display saxifrage pyramidalis. Before finally pass- 

 ing the model it should be looked at from various 

 positions ; lengthways from each end as well as 

 full front, and also from above, and again with 

 light falling at different angles. So one may judge 

 how the rock garden will appear from different 

 points, and at different times of day. When all 

 seems satisfactory a sketch should be made on 

 linen, showing the length, height and breadth of 

 each ledge not forgetting that the model is 

 twice as steep as the real thing will be. The model 

 need not then be taken on to the ground. It will 

 be useful later when the full planting scheme has to 



