THE WARDIAN CASE. 239 



plants. They may be half filled with soil, and the 

 seed sown. The daily growth may thus be watched, 

 and very many interesting lessons learned. The flasks 

 should be covered with a piece of oiled silk, so arranged 

 that it can be removed for supplies of air and water. 

 The only matter of importance in the management is, to 

 keep the rays of the sun off, or only to allow them to 

 shine very faintly, for a single hour's exposure to a hot 

 sun would bring destruction on the whole. 



It has been recommended that all Wardian cases 

 should have a double bottom, to insure sufficient drain- 

 age, as the evil most frequently experienced is sodden 

 roots, caused by standing water. This, though a good 

 arrangement, is by no means necessary. The proper 

 drainage may be secured by broken potsherds and char- 

 coal, laid along the bottom to the depth of an inch. 

 The water will, of course, drain into this, and may be 

 drawn off by a little stop-cock under the case, and hidden 

 by one of the legs. 



The depth of soil should not be greater than nine 

 inches ; too great depth will give a damp, heavy soil, 

 which will be uncongenial to the roots. 



It is also advisable to make arrangements for a com- 



