A ustic A dornmerits . 
of pebbles, and left undisturbed. In every part of the rock, and the sides of 
the aquarium, conferva should be allowed to grow, but the front glass, through 
which the view is obtained, must be kept quite clean by the occasional use of 
a sponge firmly fixed to a stick. As a matter of course, the front glass of the 
upper part should open as a door, and there should be permanent ventila¬ 
tion provided above. 
Of course, where the cases previously described occupy a sunny position, 
ferns are scarcely suitable plants to grow, as there is a danger of their fronds 
getting disfigured by the sun. In such cases the foliage plants described at 
the end of this chapter should be substituted for the ferns, with the addition 
of flowering plants in season. In both cases plunge the pots to their rims 
in. cocoa-nut fibre refuse. In shady positions give the preference to ferns. 
Flowering plants may be grown, too; but, as a rule, it will be necessary to 
change the plants frequently, as the flowers lose their freshness and beauty 
sooner in the shade than in the sun. 
As we have kept in mind the importance of light and air, we must not 
here forget that conservatories that are approached through dwelling-rooms are 
apt to communicate to those rooms more atmospheric moisture than desirable. 
Therefore, protection against damp must be thought of in time. One great 
safeguard is to establish an intermediate apartment, through which the con¬ 
servatory can be seen as well as approached. This, however, is only possible 
in certain peculiar instances. But a coating of Portland cement on all the 
walls of the dwelling that abut on the conservatory will most effectually prevent 
transmission of moisture through the walls, and a careful use of water amongst 
the plants will keep evaporation at a minimum. Succulent plants need so little 
water at the root, and thrive so well in a dry atmosphere, and, moreover, are 
so much benefited by free ventilation in summer time, that they are the very 
best of subjects for growing in window cases. Palms will bear privations 
better than is commonly believed; and a number of flowering plants may 
be kept in health for a short time on small allowances of water, provided 
they are never allowed to become quite dry. Another help towards counter¬ 
acting humidity is to have the plants staged on an open trellis, and beneath 
this a zinc tray, continued all round, and communicating with an outlet for 
the quick conveyance of every drop of water that runs through the pots in 
watering. 
