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Arsenife of lime u'lth soda. 



White arsenic pound . . 1 



Sal soda ( cn'stal ) pounds . . -1 



" Water gallon . . 1 



The ingredients are boiled in the required amount of water until 

 dissolved, which will take place in a comparatively few minutes, after 

 which the water lost by evaporation is replaced. To every 40 or 60 

 g-allons of water a pint of this stock solution and from 2 to 4 pounds 

 of fresh slaked lime are added. The chemical compound derived from 

 the combination of the sal soda and the white arsenic is arsenite of 

 soda. In the presence of lime this breaks down and arsenite of lime 

 is formed. It requires 4.4 pounds of crystal sal soda or 1.6 pounds 

 of dr}" sal soda to combine with 1 pound of arsenic and 2 pounds of 

 freshly slaked lime to combine with 1 pound of arsenic to form arse- 

 nite of lime. It is always desirable to have an excess of lime present, 

 in order to prevent all danger of burning; furthermore, this excess is 

 a convenience to the fruit growers, because they (^an see by the distri- 

 bution and amount of lime on the foliage how well the spraying has 

 been done. This formula, which is the Kedzie fornnila, with a very 

 few minor changes, has been used in many different sections of the 

 country with un^•ar^'ing success. In all of the practical tests under the 

 advice of the writer this solution is used, and is found to be not only 

 as efficient as other solutions, but far cheaper. 



Arsenate of lead. 



Arsenate of soda ounces. . * 10 , 



Acetate of lead .- do 24 



Water gallons. . 150 to 200 



The arsenate of soda and acetate of lead should be dissolved sepa- 

 rately and then poured into a tank containing the required amount of 

 water. These chemicals unite readily, forming a white flo(^culent pre- 

 cipitate of lead arsenate, which is easily kept in suspension, and can be 

 used in excessive strengths on delicate plants without the addition of 

 lime. When spra3'ed upon the foliage it forms a tilmy, adhering coat, 

 which is but little affected by ordinary rains. There are several good 

 preparations of lead arsenate upon the market. Some of these are 

 prepared in a wet state, others in a dry or powdered form. The moist 

 preparations are much preferable, because the dry powder does not 

 give such a good coat of poison upon the foliage. This poison has given 

 excellent results in use against the codling moth, but on account of its 

 expense it is comparatively little used. 



If it is desired to use Bordeaux mixture with an}^ of these solutions 

 the arsenicals are added to the Bordeaux mixture in the same propor- 

 tions as they would be to a similar quantity of water. At all times 

 the greatest care should be taken to prevent accidental poisoning with 



