THE GREEN-HOUSE. 



173 



A mode may be mentioned for destroying these 

 insects without the use of water, which, though 

 chiefly applicable to plant-houses kept at a higher 

 temperature than the green-house, may sometimes be 

 used there, especially as it kills the aphides. It is to 

 wash the flues with flower of brimstone mixed with 

 a little white wash. This is practised by that curious 

 cultivator of plants, Mr. Curator Anderson of the 

 Chelsea Botanic Gardens ; and it is said that half a 

 pound of brimstone will kill all the spiders and all 

 other vermin of the insect kind in a house one hun- 

 dred feet long and of ordinary breadth. 



Raising the temperature of the house, and water- 

 ing the paths with volatile alkali, has been tried on 

 a small scale, and is said to produce the same effect ; 

 but this is rather an expensive process. Water, 

 therefore, and chiefly applied by the syringe, may be 

 considered as the best cure for the red spider. 



A precautionary measure against this and other 

 insects may be mentioned : it is to wash once a year, 

 at the season when the plants are returned to the 

 house, all the joints and crevices of the wood-work, 

 walls, shelves, stage, and all crevices whatever, with 

 a mixture composed of soft soap and sulphur. This 

 is said to destroy the eggs which may be deposited 

 in these places. We question very much if it will ; 

 but if it does not, there can be no great expense or 

 loss of time in using it. A wash of quick-lime and 

 water Ave should think likely to do as well ; but in 

 truth we do not think that in a green-house properly 



