The sun. [volume] (New York [N.Y.]) 1916-1920, 1919-04-27

which the Bordeaux, the lime-sulphur
and the arsenate of lead are the most
complex; and II the compromising OF
these IL understood there will be no
trouble In making others.
Bordeaux Mixture.
This we'll Known remedy originated
In the province OF Bordeaux, France,
which for years has been noted for It's
grape culture and its wines.
Its discovery was entirely due TO ac-
cident. II was the custom where the
vineyards In this place adjoined the
public thoroughfare to sprinkle paris
green on the fruit nearest the highway
In order that the public, seeing IL,
would assume that the entire vineyard
was thus treated and not modest the
fruit.
There came a time when disease at
tackled and practically destroyed an en-
tire seasons product. 1t was noticed,
however. that the plants near the pub
lie road which had been sprinkled with
,aris green were not attacked by the
disease.
Investigation proved that the paris
green protected these plants from the
epidemic. Further experiments gave
evidence that the virtue OF the paris
green was due TO. the copper (paris
green is a salt of copper, and the
chemists Of France took the matter in
hand to discover what form of copper
would be best as well as cheap.
This led to the preparation OF a mix
ture OF lime and copper which we
know to-day as Bordeaux mixture. In
fact, Bordeaux mixture is unquestlon-
ably far better known to-day than the
Bordeaux wines. which it owes en-
tirely to its virtue.
In making Bordeaux mixture the in
gradients are copper sulphate (blue
vitrioD, 6 pounds; unslacked lime, 4
pounds: water. so gallons.
In. the first place 1t is NECESSARY to
have good quality OF lime. 1t will
pay to buy a good quality Of rock or
shell lime rather than risk n poor
product by using a cheap grade that
has possibly been exposed to the
weather or contains a large percent
age Of sand, clay, &C.
Dissolve the copper in about twenty
gallons of water, using small guam
t.ty of hot water first, and then adding
enough water to make the twenty
gallons. But 1t must be cold when the
lime is added. Then slack the lime by
adding II to water, and when cool
enough add water to make the twenty
gallons, and mix thoroughly. The cop
per solution will be perfectly clear, but
the lime solution will have a sediment.
Carefully pour off the clear lime
solution. leaving the sediment behind.
which can be thrown away. Now add
the lime solution to the copper, stirring
continually. which will precipitate the
copper as a whitish cloud. After mix
ing them together allow 1t to stand
until the precipitate settles, and ex-
anime the clear liquid by taking a
glassful and holding it up to light.
This should be colorless. II 1t Is blue
IT shows that the copper is not all
thrown down and the lime is weak {;
more lime must be mixed as before and
added until the clear solution Is color
less. The reason for this Is that the
blue color shows the presence Of I'M
decomposed copper sulphate, which u
likely to burn the foliage
The object of diluting before mixing
Is to have the precipitated copper as
fine as possible. The weaker the solu-
ton the finer the precipitate. Enough
water is now added to make fifty gall
Ions. Iron must not come in contact
with this solution; use barrel and
wooden stick for mixing. This is a
good general fungicide, and particu-
larly for grapevines, cooling moth and
San Jose scale, and II made in this
manner will not need any addition
such as molasses. to make it stick.