The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1886-11-08
LIGHTNING STROKES.
CAUSES OF THE SEVERE THUNDER
STORMS OF MODERN TIMES.

Effects Of the Vast Volumes of Smoke
and VapOrs Thrown Out into the At
mOsphere-A Question of Practical I'm
portance-Theory of Thunderstorms.
The researches of Professor Won Petzold,
karsten Weber, and others have proved that
the number Of damaging strokes of lightning
has considerably increased during the last
fifty years, and this increase can not be
explained by the theory that, owing to the
growing number of houses. factories, etc,
the number Of lightning strokes increased
proporticnately to the contrary, this num-
Der ought to decrease, as every building,
even when not protected by a Hghtning-rod,
effects an equilibrium of the opposite cleo
trio potentials, and, the. efore, the number
of lightning strokes ought relatively to de
crease with the relative number of build
ings. This, indeed, is proved by the fact
that in the space of one year among 10000
buildings there occurred but thirteen Gases
of lightning trokes in cities, against twenty
three strokes on buildings in the country
We, therefore, have to take this ma. ural pine
nomenoii from another point of view, and
to consider the ratio of damaging or other
strokes to the number of buildings IN a GER
tain district This ratio, called by the Ger
man naturalists bitzgefahr danger from
Iightning,) increased in the kingdom of Ba-
varia from 1874 to 1882 threetold according
to records Of insurance companies even five
foId,) and other countries show the Same in
crease.
OF GREAT PRACTICAL IMPORTANCE.
AS in nature each phenomenon must have
its cause the question arises, To what
cause is due the above mentioned factSf
And this question not only is of scientific in
terest, but also of great practical Importance.
A great many theories have already been
advanced to explain this phenomenon;
among others, that, owing to the decrease
of the woodland, houses are more and more
made the pro getting points of a certain area,
and therefore, attract the lightning; be-
sides, this decrease effects a greater rise of
temperature in summer, and, in consequence,
more numerous thunder-storms. Others
find the cause OF it in the large increase of
such constructions as gas and water-work5,
weather cocks, etc. But this theory does
not explain why, especially, country houses,
which commonly lack these kind of
structions, are mostly exposed to danger
from lightning. Admitting that these
causes may to some extent explain the IN
crease of danger from lightning, they are
not sufficient to fully show the surprising
increase of strokes during short a period
There must be a more general and tunda-
mental cause Through what can the
electrical intensity during a thunderstorm
be SO strongly increased that larger num-
Der of lightning strokes pass over to the
earth than was the case heretofores 1t is
not so much the increasing number of thun-
dsr-storms their greater force which pro
duces the increased danger.
As the main cause we now point oHt the
enormous increase, during the last fifty
years, of factories railroads, steamboats,
in short, of all constructions filing the at
mosphere with smoke, vapors and partici
of dust of every description. When we con-
slider that every day thousands or locomo-
tives. thousands of steamers go around the
earth that thousands of factories Of all
kinds daily emit enormous quantities OF
smoke, vapor aud dust into the air, that,
pecially in cities the large number Of
houses produce immense quantities OF smoke
and dust, the assertion will not seem lncred-
ib.e that there is certainly 100 times the
smoke, dust, and gases absorbed in the at
mosphere than was fifty years ago Al
ready with the naked eye the impure state
of the atmosphere may be noticed Go
through the coal districts of Manchester,
England through tho5e of Pennsylvania,
through the cities OF Essen and Pittsburg.
and you viii notice a layer of vapOr con-
stantIy 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 THEORY OF A THUNDERSTORM.
These conditions being established, we
have to consider their relations to the Vio-
lence of thunderstorms. To give the reader
q better conception of this relation we will
briefly discuss the theory Of the thunder
storm and the origin of electricity thereby
developed Friction is now generally &C
copied to be the cause of the electricity in
thunderstorm. Friction between air and
particles of ice according to Luvine), or be-
tween air and molecules of water according
to Andries is the main cause of that cleo
tricity When besides these factors parti
Giles of dust are filing the atmosphere tn
development of electricity is highly IN
creased. 1t is the ejeotion Of steam an b
ashes common to the phenomenon which
causes the thunder storms attending 1t to
assume an exceedingly violent character.
That the pyramid of Cheops is rendered
electrical by the whirling dust of the desert
NAV here also be mentioned. 1t is nothing
but the friction of the grains Of sand on the
surface of the pyramid that causes 'ctrlc-
ity to originate.
The author of this essay claims that the
rapid, enormous and lasting development
of electricity during thunderstorms can not
be otherwise explained than by purely
mechanical cause, analogous to the mechan-
ical force OF the hydro electrical machine
Now as orr atmosphere contains so much
more dust than in former years, the fact
must be of great influence regarding the in
tensity of electrical phenomena during thun-
dersUorms; from the same reasoning are ex-
planned volcanic eruptions That this in
creased force of thunderstorms must mani
fest itself in the greater violence and more
dangerous character of lightning strokes, will
te evident to the reader But there is another
cause to be mentioned 1t is an established
fact that air containing solid particles has a
conducting power in regard to electric cur
rents far superior to that of pure air. III
our day therefore, where these molecules o.
dust and solid particles fill the atmosphere
to greater extent, the latter has become a
better conductor, and favors a direction OF
the lightning strokes toward the more i'm.
pure layers in the vicinity of the earth and,
therefore, the earth itself-Chicago Times
Stettin IrOncIads for China
The two new ironcladS ordered by China
at Stettin are corvettes, partly protected by
belt armor Each is to carry four krupp
and seven Hotchkiss guns, as well as four
torpedo guns" The same correspondent
reports that Herr Krupp has now completed
his 50 ond giant gun for the Italian govern