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degree, the corn throughout France, Mens. Tillet discovered, that the insect 
which infests the grains, producing this disease, are to be killed by a degree 
of heat not injurious to the corn, and he constructed, at the expense of 
which consisted of several hundred grains, had hardly a smutted or unhealthy grain in it. T.he 
same experiment was repeated the following season, and with nearly the same result. Satisfied with 
knowing that complete washing would be found a remedy for the disease, he made no faither enquiry 
upon the subject till last autumn, when he was employed in making observations upon the blight, 
in the course of which he met wdth a good deal of smut in many fields; and being at the time 
possessed of some excellent glasses, he carefully examined some of the smutted plants. This at first 
was done more as a matter of amusement, than from an expectation of discovering any thing that 
might throw light upon the subject. Upon a near inspection wdth the glass, he found that the dirty 
green colour of the blades of the smutted ears was owdng to a number of spots, infinitely small, 
and bearing a near resemblance to those upon blighted ears: his observations were continued 
throughout the whole period of the ripening, in the course of which he made no additional discovery, 
except observing that the leaves and stalks of the smutted ears decayed sooner than such as w 7 ere 
healthy. 
About the end of autumn, however, having one day brought home some smutted ears of rather 
an unusual appearance, he examined them very narrowly, and observed that the balls were perforated 
in many places with small round holes, a thing he had not before observed in any that he had met 
with: this he ascribed to vermin ; and upon sticking one of the grains upon a pin, and placing it 
under the glass in a very bright sun, he could distinctly observe several small transparent specks 
upon the beard, or downy part of it. He examined several more, and met with exactly the same 
appearance; but being called hastily away upon business, he was under the necessity of leaving 
them upon the table, without being able to ascertain whether the objects he had seen were eggs or 
insects. In the evening when he came home, he resumed the investigation by candle-light: in 
the course of which, as he was under the necessity of holding them very near the candle, the heat 
soon relieved him from his embarrassment, by putting them in motion, and he then discovered that 
the specks above mentioned were real insects, resembling wood-lice in shape. Next day he repeated 
the same trials by sun-light with new smut-balls, and discovered the same appearances, but without 
being able to make any of the insects stir. Disappointed and vexed at not being able to see them 
in motion wdth sun-light, and recollecting the heat of the candle, he threw the concentrated rays of 
the sun upon them with a burning-glass, which completely answered his purpose of putting them in 
motion, and shewing them in every point of view. To describe minutely an insect so small as not 
to be distinguishable by the naked eye, would, says he, be no easy matter; it is sufficient to sav, 
that its general appearance is very similar to a wood-louse, though infinitely smaller. 
As soon as he was cleaily asceitamed of the existence of this insect, his mind was, he says, per¬ 
fectly at ease with regard to the cause of the distemper; but though he could very readily conceive 
that vermin, in the early stages of the growth of a plant, might so injure the stamina as to render it 
unfit to produce any thing but smut, he could not so well understand how it was possible for the 
mere touch of the black earth contained in the smut-balls to produce the same effect. 
After some reasoning he, however, gives it as his opinion that smut is occasioned by the small 
insect above described, as seen by the glass in the downy part of the grain; and that when the balls 
are either broken in the operation of thrashing, or come in contact with clean healthy grains, the 
insects leave the smutted grains, and, adhering to such as are healthy, are sown with them,’ and 
wmund the tender stem in such a manner as to render the plant incapable of producing any thin^ 
but smut. 
The grains of smutty corn are tender, and filled with a black stinking powder, instead of the 
white flour which sound grain contains. As these grains are very easily broke, they spread their 
powder on the sound grains, which having on their extremity a little tuft of hairs, the powders 
stick there. Farmers distinguish the wheat thus vitiated, by saying that it is blacked in the point, 
(in Iiench qu il a le bout) and bakers avoid it, because it gives their bread a violet or purple hue. 
