May i, 1889.] THE TROPICAL 
AGRICULTURIST. 
765 
results. It will perhaps be well to await the result 
of the experiments of this year before employing it 
on a large scale, but if its efficacy is conformed, 
the Masson process is certainly called to play a 
great part in the struggle against mildew. They will also 
doubtless succeed in making up the mixture under a 
concentrated form as in the case with eau celeste. 
The following is the mode of preparation : — 
Dissolve hot and separately; 
1 kg. of blue vitriol in 4 litres water ; 
1 kg. 300 grammes of soda ('carbon of soda of 
commerce) in 4 litres water. 
Allow these two solutions to cool. Throw the 
solution of soda into a receptacle containing about 
90 litres water. Add gradually the blue vitriol, being 
careful to stir the liquid constantly, so as to facili- 
tate the mixture of the two substances. One can 
prepare the two solutions at home, and mix the 
water only on the side of the vineyard. Avoid 
putting the sulphate of copper and the soda to dis- 
solve together hot, for it produces a vivid reaction 
between the two salts. 
(T>.) Simple solutions of blue vitriol. — Solutions of 
sulphate of copper have often been employed at 
3, 4, and 5 per mille, for combatting mildew, and 
that with a certain amount of success. But this 
simple proctss presents disadvantages : the copper 
fixes itself much less on the leaves than by the em- 
ployment of the preceding remedies, and the 
treatment has in consequence to be repeated oftener. 
On the other hand there is a rii-k of burning the 
leaves, especially if the spray be applied under a hot 
sun and if the prescribed doses be repeated. 
The solutions indicated may be applied when vines 
are being grown for furnishing grapes for the table. 
We thus avoid the disagreeable marks produced by 
bouillie bordelaise or eau celeste. But the solutions 
must be employed with precaution, and the treat- 
ment repeated from three to four times during the 
summer. The doses may be varied according to the 
growth, putting for example 300 grammes to 100 
litres of water for the first aspersion, 400 grammes 
for the second, 500 grammes for the third. 
Antiperonospora.— A manufactory of German Swit- 
zerland offers for sale under this name a concentrated 
liquid, brown coloured, of which the pretended advant- 
age is its not containing salts of copper. We see there 
on the contrary an especial drawback, and we cannot 
advise the,. employment of this substance, of which 
the efficaciousness is far from being demonstrated. 
The Chief Ingredients. —The blue vitriol or sulphate 
of copper is the essential base of all the remedies 
against mildew. It is unfortunately a product re- 
latively rather costly, and it happens sometimes that 
it is adulterated by the addition of different substances, 
especially sulphate of iron (green vitriol) or sulphate 
of zinc. It is well to examine carefully the blue 
vitriol which is delivered, which can be readily done 
in the following manner : — 
Dissolve some crystals in a glass of pure water, 
then add a small quantity of milk of lime. It 
forms a blue precipitate if the sulphate of copper 
is pure, — bluish green or rusty blue when the matter 
contains green vitriol. If there is any sulphate 
of zinc the precipitate becomes of a dirty white. 
The ammonia, for the manufacture of eau celeste 
must then be called 22° Baume. That which one finds 
is often weaker, especially if it has been kept 60 long 
while in store. 
'The Lime for the bouillie bordelaise is the fresh 
pure lime, as we have indicated above. 
The Soda (Masson process) is the carbonate of 
soda of commerce. It must be used in crystals 
Practice of Sulphurizing.— Spread the copper 
liquids with the spray prolucer so that it may be 
f^nnd scattered as equally as possible on all the sur- 
face of the foliage of the vine, such is the end of the 
operation of sulphurization. The workmen must give 
all their care, to this work : they must seek to reach all 
the leaves. Manipulating the tube of the pulverisateur : 
A fine spary should fall on the leaves ; they must not 
be sprinkled too near, nor too long, for then the little 
drops unite and fall on the ground. Walk through 
the vines with a slow and even step. Sprinkle every- 
where on the upper surface of the leaves : it is in effect 
on the leaf that the spores of mildew usually fall. 
The operation is dirty, the clothing must be in accord- 
ance. Two rows may be treated at once, but for 
persons who are not accustomed to use pulverisateurs, 
it appears preferable to treat only one row at a time. 
The clothes are soiled much less if the tube of the 
pulverisateur is held a little elevated, leaving always a 
row between oneself and the line of vines being treated. 
As a general rule, one must avoid using the pulver- 
isateur under a very hot sun, especially with eau celeste 
and the simple solutions which readily produce burns. — A 
little rain succeeding the operation is not to be feared, 
for it aids in the dissemination of the copper on the 
entire surface of the leaves— One need not therefore 
fear to spray in cloudy weather. On the other hand, 
a violent rain naturally exercises an unfavourable in- 
fluence in washing the foliage too much. 
Time of Treatment: Quantities to Apply.— As the 
development of mildew depends essentially on meteoro- 
logical conditions impossible to foresee, it is difficult to 
indicate beforehand, in a manner absolutely certain, 
when the treatment should be applied. Doubtless, 
the sulphurization must be preventive, but it must not 
be done too early for the numerous leaves which would 
develop after the operation would then not be pro- 
tected against the attack. A little while before the 
"attachment of the vines" and the "raising" it 
becomes difficult to go about among the vines without 
doing damage. On the other hand, if the branches 
are freshly impregnated with blue vitriol, persons 
occupied in " raising" must use precautious not to have 
their hands burnt. 
It seems to us then preferable, in our country, to 
delay the first treatment until after the " raising." 
But then it must be applied without delay before the 
leaves have retaken their normal position. That 
would bring us down to the end of June or the 
commencement of July. According to experiments 
made up to the present time, sulphurizatiou can be 
applied immediately before or after the flowering (it 
is s;iid even during the flowering) without injuring 
the development of the grapes in any sensible manner. 
Perhaps we may thus succeed in driving away the 
worms from the vines. 
A second treatment must be made in August, a 
little earlier or a little later, according to the develop- 
ment of the disease. Finally, if the mildew declares 
ilselt strongly, apply the treatment again at the end 
of August or at the commencement of September. 
What quantity of liquid must be applied at each 
application per pose (i.e., 4,500 sqr. metres) ? Accord- 
ing to the state of the vegetation, according to the 
number oi workmen charged with the sulphurization 
and the apparatus which they employ, these quantities 
may be varied within certain limits. On an average 
we count about 15 to 20 litres per fossorier, (i.e., 
450 metres,) which amouut to from 150 to 200 litres 
for an application. 
A trained workman can treat one pose (4,500 metres) 
each day and even more. Here again it varies much 
according to the workman and their appliances. 
The blue vitriol costs from 60 to 70 cents the kilo- 
gramme, the soda 15 cents, the lime 2 to 3 cents, the 
ammonia about 80 cents the litre. 
We thus arrive approximately at the following 
figures for the price of substances required for the 
treatment of one pose, i.e., 4,500 metres. 
For the bouillie bordelaise 4 francs: eau celeste 
fr. 1 c. 85, the mixture of soda.and vitriol fr. 1 c. 70. 
The Spraying Machines. — It is important to have 
a machine which is truly a spray producer, that is to 
say, which divides the liquids projected in five little 
drops which may cover the leaves equally on their 
entire surface. The appliance must be solidly con- 
structed, easily transportable, not too heavy and simple 
in mechanism. The receiver should be of copper, 
in sheet iron leaded or in wood. Between the sheet 
iron leaded and the copper, the preference seems to us to 
be given to the latter metal. Receivers of elliptical 
section in the shape of " boilles " are more convenient 
to carry than apparatus with cylindrical reservoirs. 
