86 THE ENGLISH FLOWER GARDEN. 



depth of that chink from which peep tufts of the beautiful little 

 Androsace helvetica, which forages has gathered the crumbling grit, 

 into which the roots enter so far that we cannot dig them out? And 

 if we find plants growing from mere cracks without soil, even then the 

 roots simply search farther into the heart of the flaky rock, so that 

 they are safer from drought than on the level ground. 



We meet on the Alps plants not more than an inch high firmly 

 rooted in crevices of slaty rock, and by knocking away the sides from 



bits of projecting rock, and laying the roots quite 

 Natural conditions, bare, we may find them radiating in all directions 



against a flat rock, some of the largest perhaps 

 more than a yard long. Even smaller plants descend quite as deep, 

 though it is rare to find the texture and position of the rock such 

 as will admit of tracing them. It is true we occasionally find in 

 fields of flat, hard rock hollows in which moss and leaves have 

 gathered, and where, in a depression of the surface, without an outlet 

 of any kind, alpine plants grow freely ; but in droughts they are 

 just as liable to suffer from want of water as they would be in 

 our- plains. On level or sloping spots of ground in the Alps the 

 earth is of great depth, and, if it is not all earth in the common 

 sense of the word, it is more suitable to the plants than what we 

 commonly understand by that term. Stones of all sizes broken 

 up with the soil, sand, and grit prevent evaporation ; the roots lap 

 round them, follow them down, and in such positions they never 

 suffer from wanf of moisture. It must be remembered that the 

 continual degradation of the rocks effected by frost, snow, and 

 heavy rains in summer serves to " earth up," so to speak, many 

 alpine plants. 



In numbers of gardens an attempt at " rockwork " has been made ; 

 but the result is often ridiculous, not because it is puny when com- 

 pared with Nature's work, but because it is generally so arranged 

 that rock-plants cannot exist upon it. The idea of rockwork first 

 arose from a desire to imitate those natural croppings-out of rocks 

 which are often half covered with dwarf mountain plants. The con- 

 ditions which surround these are rarely taken into account by those 

 who make rock gardens. In moist districts, where rains keep porous 

 stone in a humid state, this straight-sided rockwork may support a 

 few plants, but in the larger portion of the British Isles it is useless 

 and ugly. It is not alone because they love the mountain air 

 that the Gentians and such plants prefer it, but also because the 

 great elevation is unsuitable to coarser vegetation, and the alpine 

 plants have it all to themselves. Take a patch of Silene acaulis, 

 by which the summits of some of our highest mountains are sheeted 

 over, and plant it 2,000 feet lower down in the suitable soil, keeping 



