The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1895-11-09
BORDEAUX MIXTURE.
New Method OF Preparing 1t Described at
Meeting of Scientists.

New Method OF Preparing 1t Described at
q Meeting of Scientists.
At the recent meeting of the Associa.
ton Of Agricultural Scientists Mr.. Swim
gle Of the department of agriculture de.
scribed new method of preparing bor
deaux, summary of which is given by
Rural New Yorker as follows:
Where bordeaux mixture is used on
an extensive scale it pays to prepare
etock solutions Of both the copper sui
phate and the lime The stock solution
of copper sulphate is prepared by dis
solving in barrel holding 90 gallons
of water. 100 pounds Of the bluestone.
The latter is dissolved by suspending it
in sack just beneath the surface of the
liquid The usual plan is to put into
the barrel SO gallons of water and Their
mark the point where the liquid stands.
About one-third of the water is Their
poured out, and the so pounds of copper
sulphate, which has been previously tied
in coarse gunny sack, is suspended
to reach just beneath the surface of tho
liquid.
When all the copper sulphate is dis
solved, the empty bag is taken out, and
sufficient quantity Of pure water is
added to bring the solution in the bar
rel up to SO gallon mark again. 1t will
be seen that every gallon Of the liquid
contains about two pounds of copper sui
phate in solution. This stock solution is
set away in convenient place, and
when wanted is drawn from the barrel
through wooden spigot at the bottom.
The stock lime preparation is made in
much the same way. Fifty pounds of
lime are placed in barrel and then
slaked in the usual fashion When
slaked, sufficient water is added to bring
the whole mass up to previously de-
ternined so gallon mark.
The stock lime is also stored in some
convenient place, but it is best to ar
range to remove what is wanted from
the top of the barrel rather than attempt
to draw it off through a spigot.
To prepare bordeaux mixture it is
gallons Of the copper sulphate solution
and a certain number of the lime solu-
ton and mix them in some suitable
vessel Mr.. Swingle find that the more
concentrated the two preparations are
when poured together the less satisfac-i
tory will be the resulting mixture. Bor-.
deaux mixture, when made from such
oo,,,o,,tro Tod r,ro, lions 7iEo1u 10
be haky and granular and will very
soon settle. He recommends therefore
that in making the mixture both the
lime and the copper sulphate solution
should be greatly diluted before bring
ing them together. Mr.. Swingle would
prepare what we ordinarily call the SO
gallon bordeaux mixture as follows: Di-
lutte three gallons of the stock solution
of copper sulphate with water to 20 or
IS gallons. In another vessel pour two
gallons of the stock lime preparation
and dilute this with about Is gallons of
water. Pour the copper sulphate solu-
ton and the lime preparation slowly to-
gether, and then stir thoroughly for two
or three minutes with long handled,
seen that this mixture contains six
pounds of copper sulphate and four
pounds Of lime.
Mr.. Swingle suggests simple meth
cd, which, if used when the first barrel
Of bordeaux mixture is made up, would
answer until the stock copper sulphate
solution and the stock lime are exhaust
ed OF course when a new supply of the
stock preparations is made up it will be
necessary again to test the first barrel of
the mixture. All that is required to
make the test is an ordinary penknife
and piece Of emery paper. The knife
blade is inserted for couple Of minutes
in the mixture, and if there is any free
copper present it will show as a thin
film on the steel blade of the knife. If
there is no free copper present, the knife
blade will not be furnished. If the knife
blade shows the presence of copper, it is
only necessary to add small quantity
of lime. The emery paper is used sim
ply to remove the copper film from the
knife blade. Half a minutes polishing
with the paper will put the blade in
condition for another test