BORDEAUX MIXTURE 



I. ORDINARY BORDEAUX 



The composition of the mixture produced 

 by the formula ordinarily used, 4-4-50, is 

 said to be a basic sulfate of copper and lime; 

 its composition being represented by the 

 symbol, CuS04.9CuO.CaS04-3CaO. 



Procedure. — Weigh out 8 grams of cop- 

 per sulfate, dissolv it in 50 cc. of water, using 

 heat if it is desired to hasten the solution, and 

 add 350 cc. of cold water making the total 

 volum 400 cc. Slake 8 grams of quickhme 

 with a little water, dilute the paste with about 

 200 cc. of cold water and strain the mass thru 

 a piece of cheesecloth placed over a funnel 

 or a thistle tube. Dilute the milk of lime to 

 400 cc. Mix the cold solutions. 



n. WOBURN BORDEAUX 



Woburn Bordeaux may consist of either 

 of three basic sulfates of copper, the pro- 

 portions of base to acid in each being shown 

 in the following formulas: CuS04«3CuO; or 

 CuS044CuO; or CuS04.9CuO.CaS04. Its 

 most striking characteristic is the absence 



of any free lime. Either of the three com- 



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