The Daily times. [volume] (Richmond, Va.) 1886-1889, 1888-01-11
LIGHTNING STRIKES
re- RELIEVE THE ELECTRICAL TEN
SION OF THE ATMOSPHERE.
n Mysterious, Unexpected aud Fre-
quentIy Fatal 'Return stroke"-where
the Flash Takes Place and Why--Con-
ductipv Currents-High Houses.

~
auently Fatal "Retnrn stroke"-where
the Flash Takes Place and Why-Con-
Quoting Currents-High Houses.
Now. rs n charge Of electricity has the
property OF inducing another charge vi
electricity of an opposite KIM TO itself Oh
any conducting" matter near IL, ana a.
| the earth Is composed OF what Is cailea
conducting matter, it follows that u
| charged clotsi sailing over the surface OF
| the earth induces an opposite charge Oh
| the ground below. These two opposite
charges, one of positive" the other OF
'negative' electricity, tend, by another
well known property Of electricity, TO rush
toward each other and combine. Hence
when they are able 10 overcome the resist
ance of the air between, which keeps
| them apart. they leap together with a nish
and crack. producing the familiar phe-
nomena Of Thunder and lightning
Sometimes another cloud floating near
| the first one takes the place OF the earth,
| and then the lightning flash takes place
between them. Lightning of this kline
| does not strike the earth; but 1t might
have a destructive effect on the latter for
| all that. because it might give rise To the
back stroke which is sometimes fatal
To life. The back stroke is not due to
the direct flash and discharge. IL IS
rather the reaction after the direct as
charge has taken place elsewhere. sup
pose, for example, that a track OF upland
| country a rural district with trees, farms,
and here and there Il church dOtting II, IS
covered by "A thunder cloud. which induces
a charge ii electricity upon it. In order
| that the charge upon the earth may get
I nearer To that upon the cloud, so as 10
combine with it, the electricity, by another
well known property, will heap itself on
the most prominent and pointed objects OF
the landscape. That is To say, 1t VIII ac-
emulate on the trees, barns, chimney
tops and spires Of the district.
The whole atmosphere of the region Is
In a state Of tension and suspense. Inc
bolt is trembling in the balance but no
man knows where it will fall Presently
there is a binding flash of light, the SKY
is rent with a lurid stream OF FIRE, ana IN
stantly the tension is relieved. The DIS
charge has taken place ut one point the
point which offers the path OF least resist
ancc through the mir, and at which the
] electric tension was most critical At
every other place where the electricity
had seriously accumulated, there - con
seoueutly "A sudden fail of electric pOten-
tial. or "A collapse to its old condition, or,
As il is called. "A return stroke. This
Instantaneous. change is sometimes as
fatal - the direct discharge, and it may
rain a building or destroy life several
miles from the scene OF the flash. The
return stroke is therefore more mysterious
and unexpected than the flash. but fatal
effects are comparatively rare from 1t.
Nevertheless. since the latter have been
attributed TO this cause. a person cannot
feel quite SAFE, although "A thunder storm
with lightning is still several miles from
him; the number Of miles being estimated
by counting the seconds which elapse be
tween the hash and the peal, and allow
inr n distance of four miles for every
second counted. He may feel safer than
if il were close upon hiIn, but there is still
some room for fear.
In fact there is NJ real safety except
within the area properly protected by a
lightning conductor, or IN a building
which is itself a protector, for instance a
sheet iron house. Every building, then
should be protected in order 10 DE sue
I'm the country. where these are often
isolated, a lightning rod would be required
for each; but in towns one rod would
= sometimes protect more than one mouse
around it, according 10 its height and con
! ductivity.
The fash takes place at the point OF
least resistance, because 1t IS here that the
l., two opposite electricities can easiest rush
| together. But the eagerness with Whlch
4 they tend to rush together IS another
: thing to be considered. These W things
p taken together determine the discharge
There may be less resistance to the Hash
, at one house or tree than at another, but
. if the attraction between the opposite
electricitics is less at the former, the Hash
may traverse the latter house. Hence
: one cannot exactly say II one tree OF
building Will be safer than another. There
is great uncertainty, and this Is a reason
for the instinct Of awe and uneasines,
which most animals feel on the approach
OF a thunder storm.
) In general, however, We can say thal
high houses, or those perched on lngi
ground, are more likely to suffer from thC
discharge than small low lying houses
l. The former are therefore ali the more ell
. gible for protection; and they are to Dc
o avoided in seeking shelter from a storm
d So are houses surrounded by trees, anc
II with ponds or pools OF water close beside
them. For trees act as imperfect hght
IS ming rods, having a good earth connection
n and especially IL they are wet the dis
h charge may strike the house in order L
d reach the ground through them, or, in th'
q case Of the pond, through the water. On
d should not shelter under trees OF an,
il kind, but more especially tall, soft tree
k like poplars. Many deaths have been IN
" Cured from sheltering under poplar tree
in France.
Thunder storms are said TO he NOR
frequent in open, ~treeless countries, sue
as the Transvaal or the Scottish hills, an
the fact has been attributed to the I'm
- checked ascent Of electrical yapors; bu
'; on the other hand they are probably les
IL destructive in such countries.
Chiinneys, b ycreating currents OF war;
70 smoke and by their lining OF conductin
N SCOT, are dangerous parts Of houses, an
p, there ale many instances of the discharg