■378 
FERNS : BRITISH AND FOREIGN. 
examples of the superiority of this mode of growing 
plants over that of pot culture; by proper arrange- 
ment from ordinary level positions, their delicate hue 
and elegant form of outline may be seen to much 
greater advantage, as the upper surfaces of their 
fronds are generally presented to the eye more fully. 
And where this system is largely carried out, if a 
raised platform or footway be erected considerably 
above them, the advantage is still greater. The great 
beneficial influence this system has on the plant is 
mainly consequent on the more uniformly moist at- 
mosphere, so congenial to all Ferns, which can be 
successfully maintained from the great extent of the 
more natural evaporating surface of the soil, and ma- 
terial, with which the rockery is composed ; and as they 
are allowed to establish themselves at freedom in it, 
there is a similar uniformity of temperature at the 
root, as well as of moisture. As is well known, in 
large masses of earthy and other solid material, its 
temperature does not fluctuate with that of the house, 
at least, as in the case with ordinary-sized pots of soil, 
where the absorption and radiation of the heat takes 
place so much more rapidly. It may further be men- 
tioned, that, in a house entirely devoted to the cul- 
tivation of Ferns under this system, its evaporating 
surface does not wholly consist of the principal mass of 
material composing the rockwork; there is the large 
extent of wall-surface, which, if properly constructed 
with rough and absorbent material, is continually 
giving off its moisture, besides, from that reason, 
affording an excellent opportunity for Ferns of more 
•or less scandent habit to assume their native character 
in luxuriant profusion, by growing on it as on natural 
