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sparingly until the lime is completely slacked. The lime should not be 

 deluged with water. Hot water maybe used, of ten with advantage, espe- 

 cially at the outset. If too little water is added the lime will become over- 

 heated, and this is an objection. Water should be added fast enough 

 to prevent this overheating. The aim should be to produce a very 

 thick and smooth paste, which when it is afterwards diluted with water 

 will be perfectly free from lumps or granulation. A good plan for 

 the novice is to try a small portion of lime at first, and from the lesson 

 thus learned to go on to the larger matter of preparing his mixture. 

 The thick paste should be watered gradually, and not all at once. As 

 most lime contains lumps that will not slack, it is necessary to strain 

 the milk of lime after it is prepared and before it is added to the 

 sulphate of copper solution. 



It is far better to mix the two solutions in a dilute form than to 

 mix them in a concentrated form and afterwards dilute them. The 

 milk of lime should be run very gradually into the copper sulphate 

 solution, and the two liquors as they are mixed should be constantly 

 agitated. This results in a superior mixture. 



This superiority has been well illustrated in an article by Professor 

 McAlpine of Victoria, and I have secured from the Department of 

 Agriculture, through the courtesy of the Minister, the use of the 

 blocks so forcibly illustrating the non-settling properties of the 

 properly made mixture. 



It will be seen on examining the illustrations that the Mixture was 

 prepared in three different ways, and each of the three resulting 

 mixtures was placed in a cylinder and allowed to subside. The mixture 

 that stays in suspension longest is, of course, the best, the reason 

 being that it is in the finest state of division, and hence will work 

 through the spray nozzle most freely and act most efficiently after it is 

 applied to the plants. 



The two most technical parts of the process of making Bordeaux 

 mixture are the preparation of a smooth fine-quality milk of lime or 

 whitewash, and the mixing of the same with a proper amount of 

 copper sulphate solution. 



Anyone who feels uncertain about the former operation should 

 remember that there are numerous skilful preparers of whitewash 

 and that the chance to witness the operation as performed by an 

 expert is easily secured. 



Adulteration of Sulphur. 



It appears probable that sulphur is sometimes adulterated with cheap 

 forms of starch, such as unsalable flour. Samples submitted to me 

 for examination showed among the grains of sulphur much starch. 

 Sulphur mixed with starch it is almost needless to say is less effective 

 as a fungicide than pure sulphur, and when applied dry in combating 

 disease, such as the Oidium of the vine, such adulterated material 

 might lead to poor results. 



In one instance grapes showing the after effects of Oidium were 

 submitted to me for examination. I did not ascertain whether the 



