Bismarck daily tribune. [volume] (Bismarck, Dakota [N.D.]) 1881-1916, 1901-09-19
LIGHTNING FLASHES.
HOW THEY ARE EVOLVED AND THE
ENERGY STHEY POSSESS.
Inhabitants OF Compactly BuiIt
Cities Have Little Canse to Fear
These M%ysteripus and Destructive
Balls From the C1ouds.

Nj Cities Have Little Canse TO Fear
These Mysteriqus and Destrnctive
Balls From the Clouds.
Without doubt lightning was the first
electrical phenomenon that was observ-
ed by human beings. no this day it
remains the least known and least un-
Herstood OF natural electrical nantes
tations except, perhaps, the aurora.
There is q vast deal Of popular mis-
conception concerning the danger Of
lightning and the nature: Of it. The
lightning fash is a discharge from q
cloud at q high potential with refer.
ence to- the earth. When the atmos.
8phere is charged with water yaporr and
some eddy or current in it's colder up,
per strata is detected downward, caus.
Ing condensation, exceedingly minute
drops of water are formed, each bear
ing an electrical charge. The consoli-
dation of these into larger drops results
In a very great increment OF the poten-
tial Of the charge since the capacity OF
the drop varies with Its diameter and
the volume Of the drop with the cube
Of the diameter.
The consequence Of this is that it
takes, for example, eight drops co0nsoli-,
dated to make one Of twice the dame
ter Of the constituent drops, and the
charge&on the surface OF the CONSOLE
dated drop will be four times as great
as that upon the surfaces Of its ele.
lments. In this way, as the small wa.
ter particles unite to form drops which
fall as rain, the potentiaLpf the charge
they carry increases until it attainsss
enormous values, and the lightning
slash leaps to the earth, which may be:
regarded simply as a body Of very.
great ~electrostatic capacity. The dis
charge, which Is called lightning, is
apt to be more or less destructive, al
though the energy Of an Individual.
fash%is perhaps not very great. Often
the conditions are such that the dis
charge takes on an oscillating charac-
ter, producing violent surgings Of cur
rent. No very accurate measurements
have been made upon the current In.
volKed, but it Is taken to be Of the or
der of 1000 to 5000 amperes. The,
electro motive force necessary to cause
q flash a mile long is probably several
million volts, and Of course, the power
Of the fash measured In watts is very.
great, but its duration is correspond.
ingly short.
Protection Of property and life from
lightning flashes has been q subject
that has entrained the attention Of
natural philosophers since Franklin,
sent up his historic kite. The net re-
suite more than a century Of attempt
to secure protection has been the light
ming rod in its more or less inefficient
forms and the discovery that buildings
of modern construction, having metal
lie roofs and often metallic frames as
well, are practically immune from at.
tack by lightning.
The total number OF deaths due to
lightning in any given summer is com
paratively very small-in the ratio OF
about one to each 200, 900 population in
the United States. In cities the de-.
structiye influence Of lightning isex-
ceedingly small, although occasional
fires areeaused@by 1t, especially where.
gas pipes abound. #8s 4
Protection Of electric circuits from
lightning has been an interesting sub
ject for research for a number Of years,
and several highly efficient devices
have been constructed for this purpose.
Today lightning is little feared by the
station superintendent and should be.
very little feared by any me-. The
time honored rule that 1t Is wisest to
keep in the open and not seek the5sheI-
ter Q trees Is one which common pru-
dence dictates. Recourse to the feath-
er bed of our ancestors, however, is no
longer necessary. except to quiet the.
nerves Of timotous persons, while the.
ancient superstitions regarding han
ding steel Instruments aud sitting in
drafts may be utterly disregarded. a.
modern building in a city Is as nearly
absolutely lightning proof and those In
it are as nearly absolutely protected
from lightning as Is Observation-Disclosures.
al sReYieW.