On the Cultivated Potato. 
275 
the lucerne. The Scandinavians were rather behindhand, for the 
'Gentleman's Magazine' for 1764 mentions that, though intro- 
duced in 1720, the potato was not generally cultivated in Sweden 
until 1764, notwithstanding the great Linnaeus, his learning and 
industry. That destructive and continuous disease, the Curl, 
says Mr. Rham, an exact authoritv, was first noticed in this 
same year, 1764 ; during 60 or 70 vears it ravaged and devas- 
tated acres, fields, and districts. It has been well said the 
liability of the plant to disease is not the least of its peculiarities ; 
diseases date from cultivation. Partial though the affection, the 
Curl, may have appeared, it yet broke out in the same form 
in widely separated countries. Stephens,* the most practical 
writer I know, characterises the Curl as weakness : the leaves 
curl and crumple ; when virulent, they shrivel ; the tubers are 
small, and rot ; the herbaceous stems are puny, and a small 
insect feeds on the stem ; some call this the cause I A few 
plants curl one year, planted the next, half the crop will prove 
diseased : the disease is hereditary. Degeneracy is not only a 
disease, but the predisposer to acute disease, the struma of the 
potato ; Dr. Playfair says it is consumption as in overgrown 
vouth — the liability to disease is as old as the potato. With 
decay, mould or fungus there must have prevailed, indeed there 
is evidence to that effect. Microscopic manipulation, in its 
modern application, was, it must be remembered, almost un- 
known, and consequently the special character of a special 
fungus was not recognised ; but that fact has little signification 
to those who know that throughout nature there are infinite 
varieties of the same parasites ; for example, cat-fleas, dog- 
fleas, monkey fleas, human fleas, and others, all under the 
microscope different, and well known. In the ' Gentleman's 
^Magazine ' for this year, 1764, there is at page 333 an in- 
teresting paper, " Mould your potatoes up monthly," says the 
writer, "continue moulding up." In the same publication for 
1771, t there is addressed to the Society of Arts, in London, a 
most valuable memoir on a new potato, by John Howard, Esq., 
of Cardington, in Bedfordshire : this was the famous' prison 
philanthropist. High Sheriff two years afterwards, and by 
taste nearly a vegetarian. A traveller, a scientific observer, 
* ' Book (if the Farm.' 
t Philip Miller, in his ' Gardeners' Dictionary,' Edit. G, 1771. "This plant 
has been much propagated in England within thirty or forty years past ; for 
although it was introduced from America about the year 1623, yet it was but 
little cultivated in England till of late, the roots being despised by the rich, and 
deemed only proper food for the meaner sort of persons. However they are now 
esteemed by most people, and the quantity of them which are cultivated near 
London. I believe, exceeds that of any other part of Europe." He gives de- 
tailed cultural directions, and makes no mention of any disease. — J. G. B. 
T 2 
