Vermont phÅ“nix. [volume] (Brattleboro, Vt.) 1834-1955, 1878-08-09

Under what conditions is damage from
lightning possible. and what are the means
by which the risk may be lcssencd or avoided
An isolated tree, standing either upon a wild.
plain or upon an emiHcnce, il obviously like
ly to determine a lightning discharge, TO at
tract the lightning to use a common EXPIRES
sion. The top of the tree is the nearest point
to the cloud, andsiuce the tree lisa better con.
ductor than the air a line drawn vertically
through it to the cloud marks tho shortest and
easiest course along which Tie electrcties
may pass. If, when the charged cloud ar
rives directly over this point, the tension is
sufficient to overcome the resistance along
that line, a discharge will take place and the
tree will be struck But if the tension be not
sufficient, the cloud will pass harmlessly over.
Hence it appears that person standing dur
ing a thunderstorm beneath a tree so
situate is exposed to some risk. On no nc-
count, therefore, should the traveller take
refuge under an isolated tree generally he
will do well to avoid its neighborhood alto
gether; but should he be overtakeu by the
storm when on plain with no shelter near,
the tree may still be made to afford him some
protection. If he take up position near it,
but not under its branches he will probably
escape unhurt should the lightning descend
upon it. The safest distance from the tree is
that which is equal to its height To ap-
proach much nearer than this is 10 incur the
risk of being within the influence of the
stroke: to remain at a much greater distance
away Is to place ones self in the same condi-
ton of isolation rs the tree itself 1t will
have been remarked by all observers Of the
phenomenon that whenever tree has been
struck by lightning it has rally occupied
an isolated position. In describing the posi-
ton as one Of isolation, however, it is not
meant that the tree is necessarily standing
alone, but that it is not one of numerous
group. When there are many trees together
their collective conductivity is often sufficient
to cause an indestructive discharge of the
electricity. This is especially likely to hap
pen when the trees are wet with rain, for
then their surfaces are covered with a film of
water, which is a good conductor For this
reason the danger from lightning is much
less after rain has begun to fall than before
when everything is dry 1t appears, there
fore, that the safest situation during a thun-
der storm is in the midst Of wood, particu-
larry if the neighborhood of the tallcst trees
be avoided. In such place of shelter the
traveller may take refuge in full assurance that
he will there be otfectually shielded from
harm. The greatest risk of injury from
lightning is undoubtedly incurred by persons
travelling across a wide and very fiat plain
because in such a situation they are the only
elevated objects. 10 lessen the risk, which
may here be somewhat serious. advantage
shoIld be taken of whatever uuduatious Of
surface may exist. to keep upon the lowest
ground No doubt the PROSTATE position
woiii in these circumstances afford greater
cnrity than the erect. 1t happens not I'M
frequently that animals are killed by light
n.ng under tree to which they had betakcn
themselves for shelter. In these cases the
tree is struck partly in consequence of its $50
lation, and partly on account of the presence
of the animals beneath it. Usually there are
several, and often many of them assembled
together huddled probably by terror into
contact one with another. The air, heated
by their bodies, rises above them laden with
moisture, derived mainly from their breath
Who has not noticed tn cloud of vapor that
in the early morning and in certain states of
the weather hangs over a flock Of sheep or n
herd OF kline: The column of moist air as
condng through the branches of the tree to-
ward the cloud, offers in consequence of the
comparatively high conductiyity of water a
favorable passage for the electricity. herd
of cattle under nm isolated tree is thus exposed
to double risk also it is evident that these
animals are in the open country less secure
from injury than human beings, who cannot
affect the atmosphere in a like degree
(HdmbtyN'S JOlTHdk