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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 per gallon of 
fluid.) Each gallon which is taken out from the “ stock solutions 
will be equivalent, respectively, to I lb. of copper sulphate or I lb. ol 
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 all scientthc 
authorities in the United States and in our Colonies. Bordeaux mixture prepared by 
growers 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 m the 
orchard and plantation, in keeping off fungus pests from cultivated plants. According, 
however, to the recent important investigations of Mr. S. U. Pickering into 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. 1 e 
1 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/’ 
