11 



so that if any evaporation takes place it can be replaced with water. After 

 the copper-sulphate is all dissolved, each gallon of the solution will contain 

 4 Ib. of copper-sulphate. This proportion is given as an example, and can be 

 varied to suit the requirements of the maker. It is not desirable to dissolve 

 more than is required for a month's use, as it will become weak through 

 recrystallization at the bottom of the barrel and require dissolving again. 



Lime. Only good, fresh stone-lime should be used. This can be made 

 into a stock solution also. In slaking the lime, use just enough water to 

 make it slake rapidly without being allowed to powder, which indicates 

 burning through lack of water. It is advisable to watch it carefully while 

 slaking. If the lime is not of first quality, better results will be obtained 

 through the use of hot water. In this way a smooth paste should be made 

 which, when water is added, will strain readily. Dilute the milk of lime 

 with water so it will be possible to know how many pounds of stone-lime is 

 in each gallon of the lime-water. Mark to allow for evaporation as in the 

 case of the copper-sulphate solution. 



After the stock solutions have been prepared to make an 8-8-40 Bordeaux 

 mixture, proceed as follows : 



Use two barrels besides the spray-barrel. In the one barrel put 2 gallons 

 of the copper-sulphate solution, which, according to the strength of the 

 solution as described above, will contain 8 IT), of copper-sulphate. Dilute this 

 to 20 gallons by adding 18 gallons of water. In the other barrel place stock 

 solution of lime containing 8 It), of stone-lime, and dilute to 20 gallons with 

 water. Stir both these well and then pour them into the spray-barrel, so 

 that two liquids will unite as they enter. By following these directions 

 carefully a Bordeaux mixture will be prepared which will stand in suspension 

 well, stick well to the tree, and be effective. It is advisable to use this 

 mixture within a few hours after making. 



The writer has had good results from using Bordeaux mixture manu- 

 factured as follows, where a large spray outfit was in use : Place the required 

 quantity of granulated copper-sulphate (ordinary copper-sulphate ground fine) 

 in a cloth strainer and allow the water to run through this as the tank is 

 being filled. This will dissolve the copper-sulphate. When the tank is nearly 

 full, add the required quantity of concentrated milk of lime, stirring the 

 mixture well as the lime is being added. Then fill the tank full with water, 

 being sure to keep the mixture well stirred. This mixture possibly does not 

 stay in suspension as well as the one manufactured as described before, but 

 it is quicker made, requires less labour, and no difference has been noticed 

 in results in the use of the two mixtures. However, the first-given method 

 is considered the best and is generally recommended, the latter being given 

 for the benefit of those who desire to experiment to the advantage of time 

 and expense of manufacture. In the latter case never add the concentrated 

 copper-sulphate solution to the diluted lime-mixture, as it will give a poor 

 mixture as compared with the reverse method of mixing. 



It is advisable to strain the lime, especially where it contains considerable 

 sediment. For this purpose a brass strainer fixed in a cone shape in the 

 bottom of a pail with an outlet is very satisfactory. By ixniring the mixture 

 on the top of the cone it will strain readily with little clogging, and is more 

 satisfactory in this respect than a flat strainer. 



