52 The Potatoe Plague. 
of a series of scientific experiments made by him. Ie hag 
detected in the potatoe the growth of a fungus analogous te 
the mushroom family. It is usually seen as a green mould, 
and is often found in the cores of apples and the interior of 
nutshells. The seeds are invisible to the naked eye, easily 
carried about, by the wind, and penetrate wherever the air 
ean enter. Their extensive dissemination is, therefore, easy. 
When they fall on the potatoe, in cireumstances favorable to 
germination, the blight, or decay, is the consequence. The 
dry rot in timber proceeds from an analogous cause, 
‘Though maintained by several learned men, I do not deem 
this theory a very probable one. It is rather difficult to con- 
ceive a fungus alighting on the tops of a plant and thence 
growing its subterranean way downward to the tuber; and, 
when arrived there, if it ever does so artive, there is no con- 
clusive testimony that it produces decay. That a parasite 
vegetable can live and propagate itself in the capillary ves- 
sels of another vegetable, is a supposition extraordinary, to 
say the least ; and, if it descend the outside of the stalk to the 
tuber, how does it penetrate the skin and first appear, where 
one would naturally least expect to find it, in the heart of the 
potatoe? This theory has, at least, the merit of novelty, to 
recoumend it; but I cannot concede it my belief without fur- 
ther evidence. It appears to me much more likely that the 
potatoe fungus, like the supposititious potatoe fly, is an acces- 
sary after the fact; a consequence, and nota cause of the 
disease. 
here are other some, who ascribe the potatoe plague to 
the occurrence of a honey dew, a thing which, it appears, 
was known to the ancients; but is certainly so little known to 
the moderns that I am sure they will not take it as an affront 
that I tell them what it is. 
Early in the mornings of May or June, after a long 
drought, in Carolina, and after a succession of warm days and 
cool nights, there is found on the leaves of plants a fluid like 
