49 



three gallons of water, and add to this six gallons of the sulphate of copper 

 "stock solution" (or six pounds of dissolved chemical). Next, add a 

 quantity of lime paste with a shovel and stir well until dissolved. When 

 dissolved, use a testing fluid to ascertain excess or deficiency of lime. The 

 "test solution" is as follows: 



Half ounce potassium ferrocyanide (poison) dissolved in one half pint 

 of water. Fill this solution into a dropping bottle. 



Having added and dissolved the lime in the copper sulphate solution, 

 as described above, stir well the contents of the barrel and allow one minute 

 to settle, then drop a few drops of "test solution" into it. If these, on 

 striking the surface, colour the liquid brownish, add more lime, stir until 

 dissolved and test again ; if the mixture does not change colour, the solution 

 contains the proper amount of lime. 



There is no need to add accurately four pounds of lime. Lime will 

 vary in composition, hence the test above prescribed is better than relying 

 upon lime by weight. 



Finally, add to each forty gallons of spray, the required quantity of 

 Paris Green, strain through brass wire cloth strainer into pump, and solu- 

 tion is ready for spraying. Replenish stock solutions as required. 



Spray Pump. 



We use a double-cylinder, two-horse sprayer, forty gallons capacity, 

 and have found it satisfactory after careful adjustment, but there are other 

 sprayers on the market just as good. The more pressure you use, the 

 finer the spray, but the more solution is required. 



Forty gallons of solution should spray one acre thoroughly. Spraying 

 one acre takes from one and a quarter to one and three-quarters of an hour. 

 Attend to the spray nozzles; keep them free from clogging. 



