188 THE HANDBOOK FOR PRACTICAL FARMERS 



tion. If made properly, it is just as good as Paris green, and is 

 much cheaper. The best method of preparation is as follows : 



Formula for Stock Solution: 

 White arsenic, 1 pound. 

 Crystal sal soda, 4 pounds. 

 Water, 1 gallon. 



Boil these in an iron kettle for twenty minutes, or until thor- 

 oughly dissolved. The Jcettle 7nust he kept exclusively for this 

 purpose. The soluble material obtained is arsenite of soda, and 

 can be stored away in jugs or bottles, labeled ''poison," for 

 future use. For forty or fifty gallons of spray, take one and 

 one-half to two pints of this solution and four pounds of freshly 

 slaked lime. Dilute the lime and strain ; then add the stock solu- 

 tion. Pour into the spray barrel and it is ready for use. 



Bordeaux mixture. — This is made of copper sulphate (blue- 

 stone), quicklime and Avater. It is used in various strengths, the 



5-5-50 being proba- 

 bly that in most 

 common use, al- 

 though the 4-4-50 

 will probably give 

 equally good re- 

 sults. 5-5-50 sim- 

 ply means that five 

 pounds of copper 

 sulphate, five pounds 

 of lime and fifty gal- 

 lons of Avater have 

 been used in the 

 preparation of the 

 spray. In the same 

 way 2-^-50 would mean that two pounds of copper sulphate, 

 two pounds of lime and fifty gallons of water have been used. 

 The number of pounds of copper sulphate is indicated by the 

 first figure, the number of pounds of lime by the second, and 

 the number of gallons of water by the third. 



One of two methods may be used in making Bordeaux. Either 

 it may be made directly, or stock solutions may be made and 

 these stock solutions used whenever the fungicide is needed. In 

 making the spray directly, take five pounds of copper sulphate, 

 put it into a coarse gunnysack, and hang it in a barrel contain- 

 ing twenty-five gallons of water. Being suspended, the copper 

 sulphate will dissolve much more readily than if put into the 



Fig. 100.— Making Bordeaux mixture. The two men 

 pour together the diluted lime milk and the blue- 

 stone solution into a barrel or spray tank and stir 

 well. — Farmers' Bulletin 2Ji3. 



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