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APPENDIX A. USEFUL INFORMATION. 



17. — Arseniate of Copper. 



2J lbs. Copper sulphate . 

 4 gallons Water . , 



J Dissolve. 



Stock solution A. 



' ) Boil 

 ') gs 



1 lb. White arsenic . 

 5 lbs. Washing soda 



2 gallons Water 



Mix equal parts of A and B, and dilute with 35 parts of water 

 This is equivalent to lead arseniate standard solution. 



till dissolved : make up to 4 

 gallons. Stock solution B. 



18. — Kerosene and Lime. 



20 parts Lime 

 1 part Kerosene 



(by volume) ■) pi^e j-oad dust or any fine neutral 

 (by volume) > powder Mill do. 



The same mixture can be made with sanitary fluid, cheap phenyle, or other carbolic 

 fluids. 



STRENGTHS OF INSECTICIDES, 



The following table gives the weights or volumes of insecticides to be used, 

 calcukted for the kerosene tin or spraying machine holding four gallons:— 



Arsenic. — The fatal dose for an adult is from one to two grains, equivalent to 

 three to five grains of lead areeniate, obtainable by dyinking from balf to a third of a 



