200 



The Wardian Case. 



The cover is raised on light hinges, and secured from falling back by deli- 

 cate chains at the sides, as shown by the cut annexed. 



The pipe on the upper line of the frame is cut through the centre ; so 

 that half of it rises with the top, the glass being secured by thin brass 

 clamps. 



Between the glass frame and the wooden base is a zinc ventilator, about 

 two and a quarter inches square, perforated with fine holes on the outside 

 and upon the upper surface of the inside. The glass frame rests upon the 

 ventilator, which on the exterior is beautifully decorated with illuminating 

 colors, gratefully relieving the sombre character of the black walnut below. 

 The cut following will explain the ventilator better than words can do : — 



This apparatus admits air ; and the glass frame, not being air-tight, has 

 escapes enough to produce a gentle current of air through the Case : but at 

 times, for part of the day, it is well to wedge the top open half an inch with 

 a piece of cork. If moisture in the Case should become excessive, the top 

 must be raised entirely for a while. Five or ten minutes will clear it en- 

 tirely of vapor. That Wardian Cases should be air-tight is a mistake, 

 although I had some satisfaction with such a one for several years ; but, 

 in a Case where air is judiciously admitted, a much larger number of 

 plants may be successfully grown, and among them many flowering ones. 



