Iron County register. [volume] (Ironton, Iron County, Mo.) 1867-1965, 1886-07-22
LIGHTNING STROKES.
A Plausible Explanation of the Remarka
BILE Increase of Thunder-Storms.


that the number of damaging strokes OF
lightning has considerably increased
during the last fifty years, and this in
crease can not be explained by the theo-
ry that, owing to the growing number
of houses, factories, etc, the number OF
lightning strokes incre; sed proportion.
ately; to the contrary, this number
ought to decrease, as every building
! even when not protected by lightning
rod, effects an equilibrium of the oppo-
site electric potentials, and therefore the
number of lightning strokes ought rela,
lively to decrease with the relative mum
Der of buildings. This, indeed, is
proved by the fact that in the space oil
one year among one hundred thousand
buildings there occurred but thirteen
eases of lightning stroke in cit
les, against twenty-three strokes
on buildings in the country. We, there
fore, have to take this natural phenom.
enon from another point of view, and
to consider the ratio of damaging or
other strokes to the number of buildings
in certain district. This ratio, called
by the German naturalists bhtzgefdhy
| danger from Legitimacy, increased in
the kingdom of Bavaria from 1874 TO
1882 three-fold according to records of
| insurance companies even five-fold) +,
| and other countries show the same in.
crease.
| As in nature each phenomenon must
have its cause, the question arises: To
| what cause is due the aforementioned
facts? And this question not only is of
| scientific interest, but also of great
practical Importance. A great many
! theories have already been advanced to
explain this phenomenon; among 9TH
ers that, owing to the decrease of the
woodland, houses are more and more
made the projecting points of a certain
area. and therefore attract the light
nng; besides, this decrease effects a
| greater rise in temperature in summer,
and, in consequence, more nu-
merous thunder-storms Others find
the cause of it in the large
/ increase of such constructions as
| gas and water works, weather-cocks,
etc. But this theory does not explain
why, especially country houses, which
commonly lack these kind of construc.
tions, are mostly exposed to danger
| from lightning. Admitting that these
causes may to some extent explain the
increase of danger from lightning, they
are not sufficient to fully show the sur
! prisng increase of strokes during so
short period. There must be more
! general and fundamental cause.
| Through what can the electrical in
| tensity during thunderstorm be
so strongly increased that a larger mum.
| Der of lightning strokes pass over to the
earth than was the case heretofore? II
is not so much the increasing number
of thunder-storms as their greater force
which produced the danger.
| As the main cause we now point our
the enormous increase in the last fifty
years of factories, railroads, steam boats
in short, of all constructions filling
! the atmosphere with smoke, va
pors, particles of dust of every
description. When we consider that
every day thousands of locomotives,
| thousands of steamers go around
| the earth; that thousands of factories Of
all kinds daily emit enormous quantities
of smoke, vapOr and dust into the air;
/ that, especially in cities, the large num-
| Der of houses produce immense guam
| titles of smoke and dust, the assertion
will not seem incredible that there is
| certainly one hundred times the smoke
! dust and gases absorbed in the atmos-
| phere that there was fifty years ago
| Already with the naked eve the impure
state of the atmosphere may be noticed.
| Go through the coal districts of Man
chester, England, through those of
| Pennsylvania, through the city of Pitts
burgh, and you will notice layer of
vapor constantly lowering over them;
the air is filled with foul gases, and
every object is more or less covered
with the settling particles of dust.
The conditions being established, we
have to consider their relations to the
violence of thunder-storms. To give
the reader a better conception of this
relation we will briefly discuss the
theory of the thunderstorm and
the origin of electricity thereby
developed. Friction is now generally
accepted to be the cause of the
electricity in thunderstorm. Friction
between air and particles of ice (accord.
ing to Luvine) or between air and mole
cu1es of water according to Andries) is
the main cause of that electricity. When
besides these factors particles of dust are
filling the atmosphere the development
of electricity is highly increased. 1t is
the election of steam and ashes common
10 the putuOIut1lOH WHICH causes Inc
thunder-storms attending it to assume
an exceedingly violent character That
the pyramid of Cheops is rendered cleo
trcal by the whirling dust of the desert
may here also be mentioned. 1t is moth
ing but the friction of the grains of sand
on the surface of the pyramid that causes
electricity to originate.
The author of this essay claims that
the rapid. enormous and lasting devel-
;opment of electricity during thunder.
storms can not be otherwise explained
than by purely mechanical cause anal
agous to the mechanical force of the hy-
dro-electrical machine. Now, as our at
mosphere contains so much more dust
than in former years, the fact must be
of great influence regarding the inten-
sity of electrical phenomena during
thunder-storms: from the same reason
ing are explained volcanic erupdons.
That this increased force of thunder
storms must manifest itself in the great
er violence and more dangerous charac-
ter of lightning strokes will be evident
to the reader. But there is another
cause to be mentioned. 1t is an estab-
lished fact that air containing solid par
ticles has 3 conducting power in regard
to electric currents tar superior to that
of pure air. In our day, therefore.
where these molecules of dust and solid
particles fill the atmosphere to a greater
extent. the latter has become better
conductor. and favors direction of the
1ightn NO strokes toward the more i'm
pure LAYERS in the vicinity of the earth,
~. II,