762 Rejport on Prevention and Cure of Potato Disease}' 
In 1891 only a single variety was experimented upon at each 
station, but the present series was considerably more extensive, 
and the endeavour was made to secure at each station not one crop 
only, bat three different ones, representing respectively : — 
(«) An EAELT variety of potato. 
(1) A MEDIUM variety. 
(c) A LAi'E variety. 
At the same time it was felt not to be desirable to interfere with 
local considerations, and, accordingly, it Avas not laid down what 
particular varieties should be grown, but inquiries were made with 
a view of selecting those growers who would in the ordinary course 
have grown more than one kind of crop. Consequently, the varieties 
chosen were those which were in ordinary use in each locality. 
It was further arranged to have in the case of each variety of 
potato three plots set aside for the experiment, as follows : — 
Plot A for EAELY application of the louillie (before any disease 
appeared). 
Plot B for DATE application of the houillle immediately upon 
disease making its appearance). 
Plot C to he left untreated. 
The maximum size of the plots was to be half an acre, the minimum 
size one-quarter acre, and they Avere to be divided off from the rest 
of the field, and from one another by small paths, so as to keep them 
distinct. 
The composition and strength of the hoiiillie bordelaisc mi.xture 
was the same as in the preceding year, viz. : — 
20 Ih. sulphate of copper, 
10 lb. lime (imslaked), 
100 gallons Avater, 
this being, accordingly, a two per cent, strength solution of sulphate 
of copper. Particular care Avas taken to employ good and pure 
materials, more especially as some experiments conducted by other 
societies in the previous year Avere belieA'ed to have failed owing to 
the impurity of the materials used. The sulphate of copper Avas 
obtained from Messrs. Saunders, Fielding ck Co., 50 Lime Street, 
London, E.C., and Avas tested by Dr. A'oelcker previous to the send- 
ing out of ^ cwt. kegs of it to each experimenter. Samples of the 
lime locally obtained and intended to be used were also sent to 
Dr. Voelcker, Avhose examination of them proA-ed very necessary, 
as, in three cases out of the six, the samples first sent Avere un- 
suitable, they being either not properly burnt, or already slaked, or 
otherwise impure. Ultimately, good lots were obtained at all the 
stations, though in some cases the lime had to come from other 
districts. 
The machine used for distribution of the houiUie was the 
Eclair ” machine of M. Yermorel, obtained from Messrs. Charles 
Clarke ik Co., Windsor Chambers, 33 Great St. Helens, London, E.C. 
It is described in the Journal, 3rd series, Yol. II., pp. 232-3. 
