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" milk-of-lime " must be well strained, and it is advisable also to strain 

 the Bordeaux mixture before spraying. In this way we obtain 

 fifty gallons of Bordeaux mixture of the best quality. 



Two points are of primary importance in making Bordeaux 

 mixture. The first is that quicklime, in lumps, that is to say, 

 as freshly burnt as possible, should be used. Powdered airslaked 

 lime, such as is often found in builders' yards, will not make 

 Bordeaux mixture. The second point to observe is that the two 

 constituents, viz., copper sulphate and lime, are diluted with water 

 as much as possible (consistent with the formula) before being mixed 

 together."^ If concentrated solution of copper sulphate and lime are 

 mixed together, and water then added to make up the fifty gallons, 

 the resulting Bordeaux mixture will be of very inferior quality. 



Bordeaux mixture is fully efficacious only when freshly made, 

 and will not keep. If more than a day old, it requires to be very 

 thoroughly and constantly stirred while being used, and the use of 

 only freshly-made Bordeaux mixture is far more economical in the 

 long run, and is here strongly recommended. 



If a considerable quantity of Bordeaux mixture is required for 

 use, the making of stock solutions of copper sulphate and lime, which 

 can be kept through the spraying season and used when wanted, 

 saves both time and labour, and is free from all objection. The 

 stock solutions are made as follows : — Take two 50-gallon barrels. 

 In one dissolve 50 lb. of copper sulphate in exactly 50 gallons of 

 water. In the other slake 50 lb. of lime by the gradual addition of a 

 little water ; to the creamy paste thus obtained add water to make 

 exactly 50 gallons of "milk-of-lime." These stock solutions will 

 keep for months. Before the ** milk-of-lime " is used, the contents 

 of the barrel must be thoroughly stirred as the slaked lime will have 

 sunk to the bottom. (Care must be taken to stir the " milk-of-lime " 

 very thoroughly each time before measuring it out, so as to get the 

 slaked lime thoroughly in suspension. If this is done there is no 

 difficulty in obtaining the correct quantity of lime p^r gallon of 

 Huid.) Each gallon which is taken out from the *' stock solutions " 

 will be equivalent, respectively, to I lb. of copper sulphate or I lb. of 

 lime. The required amount of each stock solution is then diluted 

 with water, according to the formula given above, before being 

 mixed together. The " stock " copper sulphate solution must be 

 measured out in a wooden pail. 



The method of mixing described above is that recommended by ail scientific 

 authorities in the United States and in our Colonies. Bordeaux mixture prepared by 

 i?rowers in accordance with these instructions has long proved in these countries— and 

 more recently in England— to be of the greatest value, under practical conditions in the 

 orchard and plantation, in keeping off fungus pests fiom cultivated plants. According, 

 however, to the recent important investigations of Mr. S. U. Pickering mto the nature 

 of Bordeaux mixture, a slightly superior method of mixing the two constituents is " to 

 take the lime in as weak a condition as possible and, consequently, the copper sulphate 

 in as strong a condition as possible, and to add the copper sulphate to the lime. The 

 milk-of-lime,' after being diluted with the bulk of the water and stirred up several times 

 during about half an hour, should be left for the grosser particles to settle before the 

 copper sulphate is added to it, and, after the addition of this, very little more stirring 

 should be done." 



