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WINDOW GARBENINQ 
be far more welcome to that class of our plant lovers who have often felt the dis- 
appointment in their pot plants, many of the best of which, notwithstanding the 
closest care, will show the yellow leaves and drop off, or the buds develop 
but an imperfect blossom ; the fern case will prove to be their refuge in distress, 
a never failing source of interest and amusement. 
Principles of the Fern Case. 
Let us understand the principles of fern cases and the operation and life of 
plants witbm. Those of you who have observed plants under bell glasses 3r 
bhades, have noticed that the moisture often collects so quickly inside as to actu- 
ally obstruct or prevent the plant from being seen, and have wondered where this 
moisture came from. 
The answer to this question is simple : " From the earth, the plants, "by exha- 
lation, i. e. vegetahle "perspiratinn." But you ask again: " Wliy does it colled 
80 largely f " and we rei)ly : "Simply because we confine it, and prevent its escape 
and evaporation by making our case airtight. If the case were ventilated, its tem- 
perature would be moderated to correspond with the atmosphere of the sitting 
