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X. — Experiments on the Growth of Potatoes. Bj Lord 
PoRTMAN, President. 
Dear Pusey, — In compliance with my promise, I now report 
my progress in experiments on potatoes. 1 have ripened all the 
crop raised from diseased tubers. They were put in pots in a cold 
frame in September, and kept there until December ; then were 
shifted into 8-inch pots, well drained, and kept in a dry heat of 
65° and 70°. The whole produce was perfectly sound, and the 
greater part of the tubers are now growing in the open ground 
for a crop. One pot was, at the recjuest of Dr. Lindley, moved 
into damp heat, but kept well drained, and the produce was per- 
fectly sound, but larger and better than those in the dry heat. 
The potatoes treated with lime, as explained in my letter published 
in the last Journal, kept well, and were almost all excellent food. 
A small portion, however, was slightly diseased, and was given to 
the pigs. The potatoes planted from the crop of 1846 are in the 
state which I will now describe. 
Bryanston Field Potatoes, May, 1 846. 
Salmon kidney potatoes, planted in November in rows on the 
flat surface, and .5 or 6 inches deep. 
Lot I. Manured with farm-yard dung, and the potato sets 
planted under it. 
Lot 2. Manured with farm-yard dung, and the potato sets planted 
over it. 
Lot 3. Planted without any manure, hut in all other respects simi- 
lar to Lots 1 and 2. 
All the sets were planted whole, apparently free from disease, and 
well rolled in lime. The result of Lots 1 and '1 is bad ; not more 
than one in ten of the sets having stood the wet weather of the 
winter and spring, or the retention of so much moisture by the ma- 
nure. The sets rotted off at various times, though some, which 
afterwards rotted, kept sound till the middle of March. The con- 
dition of Lot 3 is good ; nearly all the sets have grown, and the 
plants look very healthy and are in vigorous growth. This lot was 
not manured at the time of planting, but later in the spring, by a 
top dressing of artificial manure ; the soil is dry and light on a 
chalk subsoil. 
Details respecting the Crop in Bryanston Gardens. 
Lot L Planted in dry ground, on a chalk subsoil 6 inches deep, 
without manure, but in good condition, in the first week in 
November. Wimboriie kidneys and ash-leaf kidneys; both 
sorts have conic up regularly, and arc looking exceedingly well. 
