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nest consideration, provided the amount of damage annually done by 

 this pest would seem to warrant the trouble and expense. 



How is the disinfecting to be done? A mal-odorous, inflammable 

 liquid, known as bisulphide of carbon, is the agent, and its application 

 is very simple. The simplicity of the operation depends upon the fact 

 that the liquid is extremely volatile. When exposed to the air it evap- 

 orates with great rapidity, and its vapor is sure death to insect life. 

 Prof. Doran, in the bulletin of the Maryland Agricultural Experiment 

 Station above referred to, following earlier writers, recommends the use 

 of this substance in tight bins, and when so used it is undoubtedly 

 more effective, but there is no absolute necessity for a very tight recep- 

 tacle, and it may be used to advantage in a reasonably close room of 

 any dimensions. The method is to pour the liquid into shallow vessels, 

 like small tin pans, and set them on top of the grain. The vapor is 

 heavier than air, and will sink down through the mass of grain and 

 destroy all insects. The amount to be used varies with the space to be 

 treated. When used in bins, a pound and a half to a ton of grain is 

 recommended by Prof. Eiley. When used in a reasonably close room 

 or in a nearly empty bin, one pound of the bisulphide should be evapo- 

 rated for every one thousand feet of cubic space, or in a space 10 by 10 by 

 10 feet, ^ of a pound in each of three shallow vessels for a space of these 

 dimensions. For a space 10 by 10 by 20 feet, use 2 pounds in 6 vessels ; for 

 a room 10 by 20 by 20 feet, use 4 pounds in 12 vessels, and so on. Make 

 the room as tight as is convenient. A good time to treat the grain is on 

 Saturday afternoon. Place your pans of bisulphide in position, close 

 the room up tightly before dark, and leave it closed until Monday morn- 

 ing. Then air the room thoroughly, and stir the grain to some extent. 

 The vitality of the grain Avill not be injured in the least, nor will its 

 edible qualities be harmed. 



One point should be always borne in mind in using bisulphide of car- 

 bon, and that is its extreme inflammabiUty ; its vapor when confined is 

 even explosive. No light nor fire should be brought into its vicinity. 

 With care in this respect, however, it is easy and safe to handle, and it is 

 not dangerous for a human being to inhale a reasonable amount of the 

 vapor, in spite of its extremely offensive odor — to which, by the way, 

 one soon becomes accustomed. 



There is no need to insist before this Institute upon the value of 

 concert of action in many farm operations, but in no way can the 

 results of concert of action be made of more practical benefit than in 

 the warfare against injurious insects. In regard to this specific pest I 

 feel certain that following the plan outlined will result in the almost 

 complete annihilation of the loss which it annually occasions. 



It may be of interest to repeat here the excellent recommendations 

 made by Mr. Ruffin against this insect as a wheat pest. He says : 



Wheat, as soon as reaped, and perhaps sooner, is supplied from the granaries with 

 a greater or less number of jjarent weevils to lay the earliest brood, and if it remains 



