FUNGICIDES 33 



'In a barrel or other suitable vessel place 25 gallons of 

 water. Weigh out 6 pounds of copper sulphate, then tie 

 the same in a piece of coarse gunny sack, and suspend it 

 just beneath the surface of the water. By tying the bag to 

 a stick laid across the top of the barrel, no further attention 

 will be required. In another vessel slack 4 pounds of 

 lime, using care in order to obtain a smooth paste, free 

 from grit and small lumps. To accomplish this, it is best 

 to place the lime in an ordinary water-pail and add only a 

 small quantity of water at first, say a quart, or a quart and a 

 half. When the lime begins to crack and crumble, and the 

 water to disappear, add another quart or more, exercising 

 care that the lime at no time gets too dry. Towards the 

 last, considerable water will be required, but if added care- 

 fully and slowly, a perfectly smooth paste will be obtained, 

 provided, of course, the lime is of good quality. When the 

 lime is slacked, add sufficient water to the paste to bring 

 the whole up to 25 gallons. When the copper sulphate is 

 entirely dissolved and the lime is cool, pour the lime milk 

 and copper sulphate solution slowly together into a barrel 

 holding 50 gallons. The milk of lime should be thoroughly 

 stirred before pouring. The method described ensures 

 good mixing, but to complete this work, the barrel of liquid 

 should receive a final stirring, for at least three minutes, 

 with a broad wooden paddle. 



' It is now necessary to determine whether the mixture 

 is perfect — that is, if it will be safe to apply it to tender 

 foliage. To accomplish this, two simple tests may be used. 

 First insert the blade of a penknife in the mixture, allowing 

 it to remain for at least one minute. If metallic copper 

 forms on the blade, or, in other words, if the polished 

 surface of the steel assumes the colour of copperplate, the 



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