42 
THE FLOWER GARDEN. 
Ceterach, Polypodium vulgare and Scolopendrium vulgare, 
will flourish, and in the course of years add to their number 
by means of their sporelings. On the summit of the wall 
place a few inches of a mixture of good loam and fresh cow 
dung kept in position by means of bits of stone, for the plants 
to root in. In the face of the wall make holes in the joints 
and fix the roots of the plants firmly in position by means of 
loam and fresh cow dung. Once the plants get established 
they will root into the mortar. (See Figs. 16 and 26.) 
Fig. 16. AN OLD WALL GARDEN. 
The top of an old wall transformed into a bed of soil and pieces of rock, 
to form a home for drooping trails of Aubrietias and Campanulas, and such 
plants as Snapdragons, Pinks, etc. 
Dry Stone Walls. — Where old walls do not exist, special 
dry ones may be erected in appropriate positions at the base 
of a bank, or in the neighbourhood of a sunk rockery. These 
are simply built of pieces of limestone, ragstone, or sandstone 
embedded in good loamy soil freely mixed with cow dung, no 
mortar being used. In this case ample spaces should be left 
between the stones to allow plants to be inserted. When 
completed, plant tufts of the foregoing plants in the spaces, 
fixing them in with cow dung and loam. Additional plants 
for the purpose are Alyssum saxatile and montanum, Arenaria 
balearica, Campanula fragalis and garganica, Erinus alpinus, 
