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XXV III. — On the Disease in Potatoes. By the President, Lord 
PORTM A\. 
To Mr. Pusey. 
My dear Pusey — I send you the observations which I have made 
upon the crops of potatoes grown in my garden and in my fields 
this season, which you asked me to send you for publication in 
our Journal. As soon as 1 had observed that the potatoes in 
my Gardou were diseased, I had the whole crop dug up, and found 
a great quantity so much affected as to appear to me to be useless. 
Or the worst tubers I selected a dozen from each plot of ground and 
placed them on the earth under two hand-lights, and constantly 
observed the progress of the disease. For three weeks it advanced 
rapidly, and the stench was dreadfully offensive, but at the end of 
a month no smell remained; and in six weeks I found that they 
were in the following state under each glass: — Some were quite 
dry, and crumbled to dust; some were extremely wet, and had 
the appearance of an ulcer in a state of viscous matter ; and the 
rest had put forth shoots more or less healthy. Of these last a 
few eyes had shot a length of half an inch and died, and the whole 
tuber had become wet — ulcered. The others were so vigorous 
that I cut away the sound parts with the eyes and planted them in 
pots, placing them in my hot-house. Parts of each of the pota- 
toes that grew were in the wet-ulcer state. 
These plants are now growing well, and are 18 inches above 
the pot — healthy vigorous plants; and the pots are as full of 
fibrous roots as possible : some small tubers are already formed. 
While the potatoes were under the hand-lights, there was a good 
deal of sunshine and very little rain; and 1 think that the warmth 
materially hastened the progress of the disease. Of the remainder 
of the garden crop part were stored in very shallow heaps, and 
part were spread on a dry floor ; and by carefully picking out 
all that exhibited any signs of disease, I have a good stock in a 
sound state. I found that in each of the first three weeks a few 
diseased tubers were picked out of each store, and I ordered 
a quantity of slaked lime to be shaken over the tubers, and since 
that I have found no increase of the disease. The eyes of the 
tubers are springing veiy freely, and I have planted for the crop 
for 1846 all tliose that exhibited that tendency to premature 
growth ; as I think it important for a crop to have the advantage 
of all the vegetative power of each set. The ground was dug in 
November for the winter fallow, and several potatoes were found 
in it which had not been picked up when the crop was taken off: 
none of those which were so found had decayed, though some were 
slightly diseased. 
