16 



In the bibijagua work, it is not possible to give very defi- 

 nite amounts for use. For a large mound with a centralized 

 opening, possibly one haif pound or 0.25 kilo may be efficatious. 

 For newly started colonies, possibly tvvo tablespoonsfull to each 

 is sufficient. With some, it is the custorn to pour in the charge, 

 then apply a lighted match, the idea being that the resulting 

 explosión drives the fumes to the remotest parts of the exca- 

 vation. After the charge is placed the hole should be elosed with 

 earth and tamped down. 



For destroying ants and crickets, as in the previous instan- 

 es the liquid is poured into the burroughs. 



For use against the enemies of stored producís one ounce of 

 the liquid or 28 grams is liberated in 62*¿> cubic fect or 1.75 cu. 

 metres. The liquid is placed in a shallow pan where it quickly 

 changes to a gas, and being heavier than air settles downward. 

 Henee to fumigate a bin or stored seeds the pans of bisulphide 

 are placed on the surfacc of the grain and the fumes passing 

 downward kill all animal life. The bin or room should remain 

 elosed for 36 to 48 hours. 



Extreme care should be exercised during the fumigation 

 process as the gas is highly explosive and a lighted cigar or 

 lantern taken in to the vicinity of the gas would give serious 

 results. 



HYDROCYANIC AGID GAS.— This gas is used more 

 specifically in the fumigation of houses and rooms for vermin; 

 the fumigation of nursery stock and in orchard work. Differing 

 from carbón bisulphide it is lighter than air, henee rises. For the 

 fumigation of seeds for weevil etc. we have found it very unsati- 

 sf actor v. The following is the formula for the preparation of the 

 gas, and the amounts are suitable for 100 to 150 cu, ft. or 3 to 4.6 

 cu. metres of space. 



English Metric. 



Potassium cyanide 1 oz. or 28 grams. 



Sulphuric acid 2 fluid ounces or 59 c. c. 



Water 4 fluid ounces or 118 c. c. 



