The Potatoe Plague. 108 
the crops there are beginning to fail, owing to the practice of 
planting year after year on the same soil They do not rot 
but get smaller in sive. An alkali of a very deleterious 
nature (Solanin) is found in the sprouts of potatoes which 
shoot in cellars, while not a trace of it is found in sprouts 
grown in soil. How far this tends to injure the tuber is not 
ascertained, but it is highly probable that such a tendency is 
induced. It is not probable that the degeneration of the 
tuber in one year immediately induced rot,—~by neglect, 
transformations have been going on for years, which have 
ultimately led to it. Jixperiments might easily be instituted 
to show how far shoots produced in cellars affect the crop, 
and it is certainly worth ascertaining. 
Ovrr-CuLTIvATION. What bas been said on this sub- 
ject in the foregoing pages should be re-perused with care 
and especial attention, as this is one of the main causes that 
has produced the great evil. It may be asked, indeed it will 
be asked, “If rot arises from this, and the other causes you 
have named, why has not the evil appeared before, and why 
is it so universal now?” I answer, that while the crop was 
produced by manures that are not highly stimulating, on land 
that did not contain a superabundance of nutritive matter, 
and while the quantity produced per acre was moderate, the 
disease was not developed; that in the interior, away from 
cities and large towns, there was no trouble with the crop for 
a great number of years; that in the immediate vicinity of 
cities where manure is abundant, and the land highly fed, the 
disease made its appearance in a very early stage of the cul- 
tivation of the crop, and its progress was only stayed by 
yearly importations of seed from back countries; that the 
disease has been steadily increasing for years, and it 1s not 
a new disease, but has progressively increased wherever the 
crop is cultivated; that the manner of saving and preparing 
seed, growing crops, manuring and cultivation is, and has 
