1 74 On the Prevention of Curl and Dry- Rot in Potatoes. 
evil, but have the additional advantage that after the turnips are 
sown a hand or two may easily be spared in the month of J une to 
dig or fork out the sides of hedges, corners of fields, young 
plantations, &c., which are frequently mere nurseries for weeds, 
and by planting a few bushels of potatoes in these out of the way 
places, a supply of seed of superior quality will be procured with- 
out interfering with the regular crops. They should be taken up 
whilst the tops ar^ still green. It is easy to see when a potato 
plant has done growing, and then without any loss of time, and 
before a single yellow leaf appears, the plants should be lifted. 
If it should be practicable to expose them to the sun for a few 
days before they are put by for the winter, they will keep better 
and grow more vigorously. I am quite at a loss to explain this 
fact, but I have been told by several gardeners that they have 
followed the practice for years with uniform success, and it has 
occurred to myself more than once to observe a particularly luxu- 
riant chance plant, and on taking it up to find that it had sprung 
from a green potato which had been thrown aside when the crop 
was harvested. In conclusion, I would beg to remark that, should 
my supposition as to the causes which make ripe potatoes bad 
sets prove wholly incorrect, there is, at any rate, no doubt as to 
the correctness of the facts ; and whilst the researches of philoso- 
phers are slowly but surely demolishing all erroneous theories 
and confirming true ones, we farmers may possibly turn to account 
the practical suggestions deduced from several years' careful 
observation. 
After writing the foregoing paper, a friend called my attention 
to a very able article on the potato failure by Mr. Stephens, in 
his excellent work ' The Book of the Farm,' pp. 671-674, and to 
Professor Johnston's ' Lectures,' pp. 763, 764. The latter gen- 
tleman alludes but slightly to the subject, but speaks of it as 
" highly deserving of further investigation." Both the passages 
pointed out, however, make it clear that the notion of the curl or 
potato failure being caused by overripening of the set, is by no 
means new ; and my first impression after reading them was to 
suppress my paper altogether. A moment's consitleration, ^how- 
ever, showed me that Mr. Stephens does not acknowledge himself 
a convert to the theory, though he allows it some weight, and 
Professor Johnston treats it as an open question. Under these 
circumstances I thought it best to leave my paper untouched, 
thinking that, as the experiments and chemical reasonings are cer- 
tainly new, they might be considered interesting, and, at all 
events, I shall be glad to contribute my mite in support of a theory 
which I undoubtedly consider to be the true one. 
Kirby Hall, York, March, 1845. 
