PART I.] 



CULTURAL 



Lychnis and Siline in 

 Fissures. 



Viscaria and Silene acaulis, form long tap roots, thrive 

 well in such fissures, provided the earth in the fissure is 

 continuous, and leads backward to a sufficient 

 body of soil. Where the horizontal fissures 

 are very narrow, owing to the main rocks 

 being in contact in places, and leaving 

 only irregular and interrupted fissures, such 

 plants as Lychnis Lagascce, Lychnis pyrenaica, 

 and others, bearing and preferring hot sunny 

 exposures, do well. But many plants that 

 would bear the heat and drought, if they 

 could get their roots far enough back, 

 would quickly die if placed in such fissures, from the want 

 of soil and moisture near the front; therefore it is usually 

 better, in building rockwork with these fissures, to keep 

 the main rocks slightly apart by 

 means of pieces of very hard stone 

 (basalt, close-grained ' flag/ etc.), so 

 as to leave room for a good inter- 

 mediate layer of rich loam, stones, 

 or grit, mingled with a little peat. The front view of such a 

 structure would be as above the dark spaces being firmly 

 filled with the appropriate mixture of soil before the upper 

 course of large rocks is placed. 



" As a rule, oblique and vertical fissures are both preferable 

 to horizontal ones ; but care should be taken with oblique 

 fissures that the upper rock does not overhang. A plant placed 

 at J will often die, when the same placed at H will live, because 



Horizontal Fissure. 



Right 



Wrong. 



the rain falling on the sloping face of rock at I will drop of at J, 

 and miss the fissure J altogether, while that falling on the slop- 



