NEW OR IMPROVED MEANS FOR THE PREVENTION OF ROT' IN POTATOES AND GRAPES, AND THE SIMILAR BLIGHT IN TREES, FRUITS, VEGETABLES, INSECTS, AND ANIMALS
Year: 1866

page_text: PROVISIONAL SPECIFICATION left by Charles Denton Abel at the
Office of the Commissioners of Patents, with his Petition, on the 28th
December 1866.-A communication from abroad by John Francis
Bennett, of Pittsburgh, in the State of Pennsylvania, United States of
America.
I, CHARLES DENTON ABEL, of No. 20, Southampton Buildings, Chancery
Lane, in the County of Middlesex, Patent Agent, do hereby declare the
nature of the said Invention for "NEW OR IMPROVED MEANS FOR THE PREVENTION
OF ROT' IN POTATOES AND GRAPES, AND THE SIMILAR BLIGHT IN TREES, FRUITS,
VEGETABLES, INSECTS, AND ANIMALS," to be as follows:-
The affection commonly known as the "rot" in grapes, potatoes, and the
analogous blight in other fruits, vegetables, trees, and in insects and animals,
is generally supposed to be a pestilence or disease incident to these objects.
It is well known in its blighting effects on potatoes and grapes especially, and
has by some been attributed in the case of the potatoe to the effect of
degeneracy arising from the excessive reproduction thereof from buds or eyes
cut from the tuber, while by others it is ascribed to the excessive moisture in
the ground or long continued rain..
It has been discovered by my foreign correspondent, however, that the
rot is not, properly speaking, a disease arising from a morbid condition of
the plant whose tuber or fruit is thus affected, but is an effect produced

page_text: suddenly on the previously healthy plant, vine, or tree, from without, causing
loss of vitality to some part of the plant, and thence extending from the
affected part. The grape rot generally appears first in the month of July,
when the grape has attained about half of its full size, and shows itself by
a little speck on the skin and a discolored appearance of the pulp underneath;
this occurs usually on the exposed side of the fruit. It has, furthermore, been
observed that the rot appears after and during the prevalence of thunder-
storms, or during the existence of those conditions of the atmosphere which
usually precede thunderstorms; also, that vines running on trees, escape
the rot, as also do vines situated near forest and orchard trees to a con-
siderable extent, and that vineyards which are full of weeds are less affected
by rot than those which are better cultivated. In view of the above facts,
the conclusion has been arrived at that the rot in grapes and potatoes, and
the analogous disease in other fruits, vegetables, trees, as also in certain
insects and animals arises not from a morbid condition of these objects,
but from more or less minute discharges of electricity, or, as it may be
termed, small strokes of lightning, not necessarily occuring during an actual
thunderstorm accompanied by flashes of lightning, but rather under that atmo-
spheric condition which produces the same. These discharges of electricity
which affect individual branches or berries or parts of the objects may be
very minute, and produce no immediate visible effect, and may yet be sufficient
to destroy or injure the vitality in the affected part of the fruit or other object.
This assumption, it will be seen, clearly explains the before-mentioned fact
that vines or other plants growing upon, among, or near to trees, weeds, and
other objects, and which are thus protected thereby, are more or less exempt
from the disease, as such objects serve to receive the minute discharges of
electricity. The fact that fruits which are covered with down are also less liable
to suffer from rot than those which have smooth skins is also thereby explained,
as the small hairs constituting the down serve as minute lightning conductors
which prevent a discharge of electricity from being concentrated on one point
of the fruit; also the oval podded hairy leaved and hairy stalked American
cotton plant is from the same cause less liable to be injured by the discharges
of electricity than the other species of the plant. It is a source of great loss
to the silk growers of France that at the critical period of the silkworms
laying their eggs, and of the hatching thereof, when thunderstorms prevail,
the worms and their eggs, and their young, are said to be killed by the jar
of the thunder. It is rather the aforesaid minute discharges of electricity
which destroy them.
Now the cause of the said disease having been ascertained, the present Inven-

page_text: tion consists in preventing the said discharges of electricity from taking effect
by the use at the localities where the plants and other objects to be protected
are situated of metallic rods or conductors placed at suitable distances apart,
and of a proper height above the ground, which will vary according to the
nature of the crop, plant, tree, or living object to be protected, such height
being by preference about one and a half times that of the plant or other
object, while the distance apart of the conductors should be about equal to
their height. For this purpose it is proposed to use straight rods of wire,
say three-eighths of an inch in thickness, made of iron, copper, or iron
coated with copper, and having pointed tops. Where grape vines are trained
to wire trellises, these rods may be attached to the wires, or the vine may be
supported upon copper coated iron stakes having arms attached for conducting
away the electricity.