THE ROCK GARDEN 157 



handle should be procured, and by preference 

 they should be quadrangular, though only very 

 roughly so. 



Professional constructors sometimes use an 

 artificial stone made on the spot, by plastering 

 a coloured cement over a basis of rough brick- 

 work. I have seen some very clever work of 

 this kind, indistinguishable from a natural 

 out-crop of rock, and, for all I know to the con- 

 trary, it may serve excellently. But unless 

 done by skilled hands accustomed to imitating 

 the form and stratification of the natural rock, 

 it would be a failure. I have seen it suggested 

 that good imitation rocks may be made by 

 coating brickyard waste with Portland cement. 

 The objection to these processes is the liability 

 of the artificial surface to be flaked off by frost 

 or rough usage, thereby exposing the fraud. 



Soil In this particular we cannot do better 

 than follow nature. We have seen that in 

 alpine regions the crevices in the rocks become 

 filled with fine debris, the disintegrated par- 

 ticles of the rock itself, and therefore contain- 

 ing small stones and sand, with which, of course, 

 is associated humus derived from decaying 

 plant life. This, then, suggests an artificial 



