862 QUEENSLAND AGRICULTURAL JOURNAL. [1 May, 1899, 
should be used when made, and not kept. A stock solution of bluestone and — 
a stock solution of milk of lime can, however, be kept and mixed together to 
form Bordeaux mixture as required.” p 
In a Bulletin (No. 13), January, 1897, on “ Spraying,” issued by this 
Department, Mr. Benson gives the following directions for preparing Paris 
green and Bordeaux mixture :— 
BORDEAUX MIXTURE—A FUNGICIDE. 
Winter Strength.—6 lb. bluestone, 4 lb. of unslacked lime, 22 gallons of 
water. 
Summer Strength.—6 lb. bluestone, 4 1b. of unslacked lime, 40 gallons of 
water. 
Prepare as follows (for the 40 gallons solution, the 22 gallons solution in 
proportion ) :— 
1. Dissolve 6 Ib. of bluestone in 20 gallons of cold water in one cask, 
by placing it in a bag and suspending it in the water. ; 
2. Slack 4 lb. of unslacked lime in another cask slowly by first pouring 
about 8 pints of water over it. This will reduce the lime to a thick 
cream free from lumps. Water should now be added, stirring well 
till there are 20 gallons of milk of lime in the cask. 
8. Stir the milk of lime up well, strain it and pour the whole of the 
20 gallons of milk of lime and the 20 gallons of bluestone water 
together slowly into a third cask, stir well for three minutes, and. 
if properly made the mixture is fit for use. 
The mixture is much better if made in this manner than when a strong 
solution of bluestone and lime is first mixed together, and water to make up 
the required quantity is afterwards added. 
In order to see if the mixture is properly made, plunge the blade of a 
knife into it for a minute. If the knife is untarnished, the mixture is all 
right; but if the knife is stained a coppery colour, then more milk of lime must 
be added. 
The mixture should always be neutral, as if there is an excess of bluestone 
it is apt fo injure the foliage. Use water that is free from iron, and do not 
make the mixture in iron, zine, or tin vessels of any kind—wood is the best. 
If desirable, a stock solution of bluestone may be kept on hand for use as 
required. Sucha solution may be made by dissolving 100 lb. of bluestone in 
50 gallons of water. Place the 100 lb. of bluestone in a bag and suspendit in 
the cask of water, and in the course of a couple of days the whole of the blue- 
stone will be dissolved, and each gallon of the solution will contain 2 lb. of 
bluestone. \ 
To make the 40-gallon solution you therefore take 3 gallons of the stock 
solution of bluestone and add 17 gallons of water to it to make up the 20 
gallons of bluestone solution for mixing with the 20 gallons of milk of lime as 
reviously described. A stock solution of milk of lime can also be made, butit 
is better to make it as required. 
Bordeaux mixture is a fungicide, and it is of little value as an insecticide, 
It, however, combines well with arsenical poisons, in which state it is a very 
good combined spray. : 
INSECTICIDES. ° 
Paris Green.—This is the best remedy for all insects that actually devour 
their food. It is a powerful arsenical poison, and a good sample should 
contain at least 50 per cent. of arsenious acid. It is generally used by itself, 
but if desired it can be used with lime, in the proportion of 1 1b. of Paris green 
to 4 lb. or more of lime. Mixing it with lime tends to make it less dangerous 
to handle, and will not interfere in any way with its action. It can also be 
used in conjunction with Bordeaux mixture. The best way to mix Paris green 
with water 1s to place it in a cup or billy with a little cold water and thoroughly 
moisten every particle the same way as mustard is mixed up for table use; then 
add more water gradually, stirring well whilst doing so, till it is thoroughly 
