390 
FERNS : BRITISH AND FOREIGN. 
advisable to close the ventilators for a short time 
during* the day. The glass case should be entirely in- 
dependent of the soil-box, but to fit the inside, resting* 
in a groove or rabbet. The box should be about 6 in. 
deep, and may be made of zinc, brass, or wood lined 
with gutta-percha or zinc ; but metal of any kind in 
contact with the earth or air in which plants are- 
grown is not genial to either their roots or foliage. 
I have always found the plants succeed best in a 
neatly-made wooden box lined with pitch, having- 
a small tap or cock in one corner of the bottom, for 
letting away any excess of water ; but this will not 
be necessary if proper attention is observed in 
supplying the plants with a sufficient amount of 
water at one time, which, in consequence of little or 
no evaporation taking place, will be seldom required. 
This knowledge can only be gained by practice 
many amateurs’ failures with Ward’s cases being 
caused mostly by giving too copious waterings at 
certain stated intervals. 
The height of the stand must be regulated accord- 
ing to whether the plants are to be viewed in a 
sitting or standing position ; for the former the 
ordinary height of a table is a sufficient guide, and 
for the latter a few inches higher, so that the plants 
can be seen through the side glass rather than from 
the top. In preparing the box for the plants, about 
one inch of its depth should be filled with sand or 
other drainage material, such as is already explained 
in pot-culture — but in Ward’s cases this is only 
necessary as a precaution against an over- supply of 
water, — the rest filled with soil, which should be good 
fibry peat and silver sand, intermixed with pieces of 
