PLANNING AND BUILDING 23 



causes to fall upon all and sundry, the smoky, tarry 

 products of the countless London chimneys. These 

 dirt particles stick to the foliage of the little plants, 

 and especially those with silky leaves such as many 

 of the Androsaces, and would in a short time poison 

 them if due precautions were not taken to intercept them. 



It will be seen from the foregoing brief description 

 of Alpine versus Garden conditions that it is essential 

 in our Rock Garden to provide for very ample drainage, 

 so as to modify the otherwise sodden state of our soil 

 during the winter, while every effort should be made 

 to prevent the earth drying up in summer, by using 

 pieces of absorbent stone as large as the proportions 

 of our garden will permit, to retain the mounds of 

 earth, which latter should be of a gritty nature, well 

 mixed with pieces of broken stone, or in default thereof, 

 broken brick. 



It is a well known fact that lumps of stone in the 

 soil will retain much more moisture than an equal 

 quantity of soil alone, and yet at no time be sodden. 



Where possible a water supply should be laid on to 

 various places, so that a small dribble of water can be 

 allowed to thoroughly soak the ground in times of great 

 drought. It is worse than useless to sprinkle the 

 surface, though if a permanent supply cannot be 

 arranged, much can be done by the judicious use of a 

 hose. 



