124 The Fruit-Growers Guide-Book 



vary with the brand, and they need to be used according 

 to the directions which accompany each brand. Where 

 small quantities are needed there is a distinct advantage 

 in using the commercial brands, but where large quantities 

 are needed, and especially if a steam boiler is available, the 

 home mixture may be the cheapest. 



Carbon Bisulphide 



This is a heavy, volatile liquid used largely for the de- 

 struction of insects in stored grain. The fumes are very 

 inflammable and caution must be taken to keep the liquid 

 away from a flame, or even a lighted pipe. It has a very 

 unpleasant odor and comes in large tin cans holding va- 

 rious quantities as desired. It needs to be used at the rate 

 of 1 pound to every 1,000 cubic feet of space. The fumes 

 of this liquid are heavier than air, so the liquid should be 

 placed in shallow pans on the top of the bin of grain, and 

 the bin should be as tight as possible. It is best to cover 

 the bin with a canvas to keep the fumes in, and should not 

 be uncovered or air admitted for 24 hours. 



Hydrocyanic Acid Gas 



Sulphuric acid, commercial, 1.83 sp. gr., 2 fluid ozs. 

 Potassium eyanide, 98 to 100 per cent, 1 ounce. 

 Water, 4 ounces. 



Pour the water into an earthen dish and add to it the 

 sulphuric acid. Do not pour the water into the acid, as it 

 will' spatter and burn the hands or clothing. Weigh out 

 the cyanide and put it into a paper sack, being careful to 

 not inhale any of the fumes that come from it, as they are 

 highly poisonous. Place the vessel in the position desired, 

 then drop in the paper sack of cyanide and leave the room 

 immediately. The gas is liberated very quickly and is 

 deadly poisonous. 



For nursery stock in the dormant condition use the 

 above quantity for every 100 cubic feet of space. The house 

 or fumigating box should be as tight as possible, and the 



