23 



The principie variations in the preparation of Bordeaux 

 mixture in large lots from the method just deseribed are that 

 the copper sulphate is usually dissolved in quantity and after 

 the lime requirement has been determined for a single slaking 

 of lime, the test is dispensed with as long as that particular lot 

 of limo lasts. If the test is omitted a slight variation in the 

 mixing process is found more convenient. 



For dissolving the copper sulphate in quantity, a receptacle 

 is partially filled with a known quantity of water and as many 

 pounds of sulphate are taken ;is there are galloris of water and the 

 mass suspended in the water as previonsly deseribed. After. the 

 sulphate has dissolved, one gallón or 3.81itres of the groen solut- 

 ion will contain one pound or .46 kilos of the sulphate and as 

 many gallons are used in the preparation of the Bordeaux as 

 there are pounds of the sulphate desired. 



For preparing 50 gallons or ]!><) litres of the full strength 

 Bordeaux, six gallons <>!• 22.8 litres of the copper sulphate solut- 

 ion is diluted lo 25 gallons or 95.5 litres and the required 

 amount of lime paste is stirred up with 25 gallons or 95.5 

 litres of water. One mixture may be poured into the other, 

 meanwhile stirring rapidly of both may he thrown simultan- 

 eously into a third receptacle as shown in the accompanying 

 illustration. (Fig. 6). 



Figure 6 



As previonsly stated the proportion of copper sulphate so- 

 lution given in the foregoing formula is for the strongest Bor- 

 deaux. It is advisablee to use the mixture at this strength upon 



