176 THE ORCHID REVIEW. [JUNE, 1922. 
producing that genial and moist atmosphere so essential to the welfare of 
the plants. Of course, a floor of this kind can be flooded with water, which 
is then unpleasant to walk upon, and it can be frequently damped, if anyone 
is home to carry this out, but in either case tiles dry very quickly. So 
detrimental have these glazed tiles been found in some houses that their 
entire removal has been effected, and porous bricks have been placed in 
their stead. A modified plan may, however, be adopted by removing the 
tiled floor from under the staging and making there a bed several inches 
thick of clinkers and broken coke. The tiles in the centre of the house are 
left as a pathway. Where several Orchid houses are in use, the conserva- 
tory is often kept as a show house for plants in bloom, and in this case the 
atmospheric conditions are not quite such an important item, for during the 
period of flowering new growth is rarely being made. 
Considering the greenhouse built expressly for growing plants, every 
means must be used to assist the growth by maintaining at all times a 
suitable atmosphere. And here a lesson may be learnt from the nursery- 
man, who perforce must study economy. He uses all the waste material 
from the stokehole for repairing the paths. Almost every week fresh ashes 
are scattered over the surface, so that in a short time there is a sufficient 
depth of porous material which, when charged with water, keeps the air 
almost saturated with moisture. 
No precise amount of atmospheric moisture can be stated; very much 
must be left to the intelligence of the cultivator. While the majority of 
Orchids delight in considerable atmospheric moisture during their period of 
growth, there are a few which succeed better under somewhat drier condi- 
tions. It has already been said that the nurseryman keeps his houses very 
moist, but while he on this account obtains successful results with almost 
all a it is not always so with regard to Odontoglossum grande. It 
isa noteworthy fact that many of the finest specimens of this Guatemalan 
species have been produced in amateur’s houses, and this is no doubt due 
to the comparatively drier conditions there prevailing. Should any amateur 
desire to cultivate only this plant, and the very few others that like similar 
conditions, then the conservatory type of house may meet all the require- 
ments. The majority of amateurs, however, are very fond of the Colombian 
type of Odontoglossum, including such popular plants as O. crispum and 
its ecg hybrids, and for them much moister conditions are desirable. 
Cymbidiums and Cypripediums are both very popular, and while not 
Fequuing high temperatures, a moisture-laden atmosphere is for them very 
essential. One must always bear in mind the fact that plants of the latter 
genus do not possess pseudobulbs in which reserve food and moisture ca? 
Ss Sag Blame made use of when necessity arises. Hence 4 
rought is to them a serious matter. 
