On the Means of Destroying the Red Spider, fyc, 127 



dispersed. The receptacle is then closed with a lid, the front sur- 

 face of which is perforated with many small holes, through which 

 the air impelled by the bellows passes, carrying with it a portion of 

 flowers of sulphur. By shaking the bellows, the feathers are made 

 to change their position, by which many successive portions of 

 flowers of sulphur are made to escape, till the whole which the 

 receptacle contains is expended. 



I first employed this instrument in the last summer in my melon 

 house, in which, upon some of my plants, I observed a large num- 

 ber of Red Spiders. After using it I noticed with a lens, in the 

 web, an immensity of minute particles of sulphur, in company with 

 a very large number of Red Spiders ; but upon examining my plants 

 three days afterwards, I found the particles of sulphur alone re- 

 mained, and that the Red Spiders had either died or marched ofK 

 I found no difficulty in causing many minute particles of sulphur 

 to adhere to the under surfaces of the leaves of all my plants, and 

 during the remainder of the summer I was not able to find a single 

 Red Spider upon them. 



The form of the instrument for melon plants growing in hotbeds 

 requires to be considerably altered ; and the perforations for per- 

 mitting the escape of the flowers of sulphur should be lateral, instead 

 of being in the front of the lid ; that should be made slightly conic, 

 and of less width than the receptacle, so as to come within it to a 

 small depth ; by which means the whole of the flowers of sulphur 

 that escapes will be impelled forwards. The apertures should 

 be confined to one side of the lid, which should not sink wholly 

 into the receptacle ; and through such apertures the flowers of sul- 

 phur will be made to escape below the level of the leaves of the 

 melon in the common frame, and be dispersed over the under sur- 

 faces of its leaves. 



I applied flowers of sulphur in several other cases, in the last 

 summer and always with success; and I am applying it to my 



