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Directions for making. — If large quantities of Bordeaux mixture are 

 to be used, stock solutions of the bluestone and lime should always 

 be prepared, thus saving the time necessary to dissolve the materials. A 

 stock solution of the copper sulphate may be made by dissolving it at 

 the rate of 1 pound to each gallon of water. Fill a 50-gallon barrel two- 

 thirds or three-fourths full of water, and place a sack (or box with 

 perforations in the bottom and sides) containing 50 pounds of copper 

 sulphate in the upper part of the barrel, suspending it by a string or 

 copper wire. In from twelve to twenty-four hours the sulphate will have 

 entirely dissolved, and the sack or box should be removed and enough 

 water added to fill the barrel. After slight stirring, the solution is 

 ready for use. The stock lime may be prepared by slaking 50 pounds 

 in a barrel or other vessel, and finally adding water to make 50 gallons. 

 In slaking the lime, sufficient water should be used to prevent burning, 

 but not enough to drown it, and the mass should be continually stirred 

 with a shovel or spading fork until a thin paste is formed. Stock 

 preparations of both the lime and bluestone may, during warm 

 weather, be prepared at twice this strength, that is, 2 pounds to each 

 gallon of water, but it is difficult to slake more than 50 pounds of lime 

 in a barrel, and when a larger quantity is to be prepared a box in 

 which the lime may be spread out should be used. Barrels containing 

 stock solutions should be kept tightly covered to prevent as much as 

 possible the evaporation of the water, which would give a more con- 

 centrated stock solution. Preparatory^ to use, any water known to 

 have been lost by evaporation should be added, to maintain the proper 

 strength. In making Bordeaux mixture take the necessary quanti- 

 ties of the stock copper sulphate and the stock lime solutions to give 

 the formula in the total amount of water to be used, and place each in 

 separate elevated dilution tanks, which should hold half as much as 

 the total capacity of the spray tank. Thus, if the spray tank holds 

 200 gallons each dilution tank should hold 100 gallons, and according 

 to the above formula 20 pounds of copper sulphate (20 gallons of the 

 stock solution) and 20 pounds of lime (20 gallons of the stock solution) 

 would be required. To each dilution tank, water should be added 

 (one-half the total amount of spra}^ and, after stirring, the diluted 

 ingredients are allowed to run through separate hose or troughs 

 attached to faucets at or near the bottom of the tanks, into the 

 strainer on the spray tank, where the two solutions come together, 

 producing the Bordeaux mixture; or, the diluted solutions may be run 

 directly into a mixing tank alongside, the Bordeaux mixture being- 

 conducted thence by a hose directly to the spray tank. In extensive 

 operations the latter method is perhaps to be preferred, as more than 

 one batch of the Bordeaux mixture may be prepared somewhat in 

 advance of the arrival of the spray wagon, eft'ecting a slight saving in 



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