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CARBON BISULPHIDE. 

 For Granary Insects, White Ants, Clothes Moths, etc. 



This is a colourless liquid that an exposure to air forms a poisonous 

 bad-smelling vapour which, being two to three times heavier than air, 

 spreads chiefly downwards. Vapour is inflammable and explosive, hence 

 liquid must be stored in air-tight vessels, and no naked light, not even 

 burning tobacco, brought near where being used. Liquid or- 

 dinarily sold by weight; one pound measures about 12^ fluid ounces or half 

 a wine-bottle. Insects are increasingly resistant to vapour as temperature 

 falls below 70 degs. Fahr., and treatment generally unsatisfactory below 

 60 degs. Fahr. 



Have grain in tanks or other receptables that will be practically air- 

 tight when closed, and allow for vapour filling entire enclosed space. For 

 grain in bulk, use at least 8 pounds (5 pints) per 1,000 cubic feet, increas- 

 ing amount to double or more if conditions unfavourable. Sprinkle over 

 grain; but if depth over five feet, insert equal portions at equal depth, 

 intervals not exceeding five feet to ensure good distribution of vapour 

 throughout grain. Use thin pipe with funnel at top to carry liquid 

 to required depth, making insertions abcyt five feet apart. For grain in 

 bags (200 lb.), use two to three fluid ounces per bag, preferably insert- 

 ing it through a pointed perforated pipe. Work quickly, and get space 

 closed without delay to avoid unpleasant effects on person. Cover close- 

 ly as by several thicknesses of bagging weighted with boards, guarding 

 particularly against leakage of vapour from beneath. Leave vapour to 

 work at least one day, preferably several. Vitality of grain not injured 

 even if vapour retained several weeks. Be careful about lights until place 

 thoroughly ventilated. 



For clothes moths, book insects, etc., put articles loosely in tight box 

 and expose liquid in shallow dish placed above them, using at rate of 

 one fluid ounce to three cubic feet. Keep closed several days, pasting 

 heavy paper over any cracks. 



For white ants, punch hole about a foot deep into nest, pour to bot- 

 tom four to six fluid ounces, and then cover orifice securely with soil. 

 For ants in definite underground nests, pour a few ounces through funnel 

 down every hole where ants are seen, and close holes. Avoid excessive 

 use near valuable plants, as vapour is a plant as well as insect poison. 



PROPRIETARY INSECTICIDES. 



Proprietary remedies, other than 'a few specially valuable ones of 

 known composition, are omitted from individual mention because it would 

 be invidious to mention some and not all, and because secretly com- 

 pounded articles are liable to unannounced alterations in ingredients that 

 profoundly affect their efficiency. In general the remedies advised are 

 more reliable and vastly cheaper than secret compositions sold for the 

 same purposes, but it is sometimes preferable for the small user to employ 

 the latter on the score of convenience. In making a selection, remember 

 that the greater the variety of troubles an article is advertised to cure, 

 is its probable efficiency for any particular pest. The powder 

 Katakilla" seems to be meritorious for use against aphides, and 

 also against exposed caterpillars, especially hairy ones, when arsenicdls are 

 inadvisable. 



COMBINATION SPRAYING. 



Bordeaux mixture may be applied with arsenate of lead, arsenite or 



)da, and Paris green, and if lime is not in excess, also with resin or 



oap washes; but it is inadvisable with tobacco or oil mixtures, and trees 



sprayed with it should not be cyanided for several months. Lime-sulphur 



