Fungicides 



Tessel must not be used.] Into another vessel put 

 4 lbs. of good quicklime (unslaked Mme) and slake 

 it by adding water, gradually at first until the 

 lime crumbles, then more quickly so as to form 

 a milk. Next morning, when the milk of lime is 

 cold [both liquids must be coldj, strain it through 

 a coarse cloth so as to remove all lumps, into 

 the copper sulphate solution, stirring weU mean- 

 while. When nearly aU the milk of lime is used 

 allow the mixture to settle a httle, then test the 

 clear liquid from the top by adding a drop to a 

 drop of potassium ferrocyanide on a white plate. 

 If no red colour is produced the mixture is fit for 

 use, but if a red colour is formed, more milk of lime 

 must be added until the clear liquid gives no red 

 colour with potassium ferrocyanide. When no red 

 colour is produced by this test, it shows that all the 

 copper is combined and the risk of burning the 

 foHage is reduced to a minimum. The mixture 

 should be of a blue colour if properly prepared, and 

 the fine powder to which the colour is due should 

 be slow in settling out. Make up to 40 gallons with 

 water, and make afresh whenever it is wanted. 



This is the most generally useful and most tried 

 fungicide, and is in wide use in all civilised countries. 



Soda-Bordeaux or Burgundy Mixture. — Dissolve 

 10 lbs. of copper sulphate in 25 gallons of water in 

 the way recommended above. Dissolve 11^ lbs. 

 of washing soda in another 25 gallons. When both 



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