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the tissues of the berry, that this parasite was propagated by minute 
spores which were at all times present in the vineyard only awaiting 
suitable conditions of moisture and heat and contact with the growing 
fruit to cause infection. These facts once demonstrated it was readily 
understood why bagging prevented the rot, as by that process the spores 
were simply excluded and infection thereby made impossible. Having 
reached this stage of the investigation, the question arose as to whether 
there was not some substance or substances which if applied to the 
fruit would prevent the spores from germinating or destroy them en¬ 
tirely, thereby preventing infection in practically the same manner as 
with the bags. 
The questions to be considered in this connection were numerous and 
difficult of solution. It was necessary that the substance employed 
should not injure the fruit or foliage, that it should be cheap, easily ap¬ 
plied, and above all things practicable, and, finally, that it should not 
render the fruit unfit for eating or wine-making. The good results 
obtained in treating mildew with the sulphate of copper compounds 
was a sufficient reason for giving these preparations a thorough trial 
for black-rot. Accordingly the first systematic experiments, made with 
a view of determining the value of the copper remedies for the disease, 
were undertaken in the summer of 1887. The experiments were made 
over a very wide area, and, while the results were by no means conclu¬ 
sive, they were of such a nature as to warrant a further continuance of 
the treatment. 
In 1888 the experiments were repeated on a more extended scale, and 
as a result it was demonstrated beyond question that in a favorable or 
even ordinary season from 40 to 60 per cent, of the crop could be saved 
from rot. These trials also showed that of all the preparations used 
the Bordeaux mixture, containing 6 pounds of sulphate of copper and 
4 pounds of lime to 22 gallons of water, yielded the best results. It 
was further demonstrated that the applications to be successful must 
be applied early; in fact this was to be expected from what was already 
known concerning the proper time for bagging the fruit. 
This year among other things we planned an experiment designed to 
throw some additional light on a number of questions in connection 
with the treatment of black-rot; chief among them were the following: 
(1) A comparison of the actual cost and results of the treatment, 
using the preparations known as eau celeste, Bordeaux mixture, and the 
ammoniacal solution of carbonate of copper. 
(2) The proper strengths of the preparations, i. e. the strength which 
would give the best results. 
(3) The proper time to apply the remedies. 
(4) The effect of winter treatment, i. e. spraying the vines before 
the leaves start. 
The vineyard selected for the work was situated near Eastliam, Va., 
and was the property of Mr. A. L. Hoi lad ay, who, it is proper to state, 
