The Houston daily post. [volume] (Houston, Tex.) 1886-1903, 1902-01-03
FACTS ABOUT LIGHTNING.
Common Errors as to Its Nature and Its
Destrouctiveness.

Common Errors as to Its Nature and Its
DestrouctVeness.
Electric Review.
Without doubt lightning was the hrst
electrical phenomenon that was ever OBJ
served by human beings. To this day It
remains the least known and least under
stood OF natural electrical manifestations,
except perhaps the aurora.
There is a vast deal of popular misconcep-
ton concerning the danger of lightning aud
me nature OF Il. The nghtniug dash is a
discharge from n cloud at Il high potential
with reference to the earth. When the at
musphere Is charged with water, yapOr and
some eddy or current In Its colder upper
state is ueaected downward, causing CON
densation, aud exceedingly minute drops of
water ate formed each bearing an cleo
trCal charge. The consolidation OF these
into larger drops results In Il very great
Increment OF the potential OF the charge,
since the capacity OF the drop varies with
It's diameter and the volume OF the drop
with the cube of the diameter.
The consequence Of this Is that II tak-s,
for example, eight drops CONSOLIDATED 90
make one of twice the diameter of the con
sutuent drops, and the charge On the sur
face of the consolidated drop will he four
times as great as that upon the surluce
of It's elements. In TINS way, as the small
water PARTICLES unite 10 form drops which
fail as rain, the potential OF ~ charge they
carry increases until II attalnS enormous
values,
eurth, which may be regarded SIMPLY as
IA body OF very great eectrostdtlc c9aclty,
This discharge, winch Is called hSntnin8,
is apt to be more or less destrucdye, al
though the energy of au individual hash Is
perhaps not very great.
Often the conditions are snch that the
discharge tickets on an oaGlllatlng ehafac-
ter, producing violent suIeings OF current.
No very accurate measurements have been
made upou the currents involved, but IL Is
taken 10 be of the order Of 100 to 1DO1
amperes The electrO-motlye lorce neees'
sary to cause a hash a wNe long Is prob
ably several million volts ana, OF course,
the power of the dash measured In watts
is very great, but Its duration Is CORE
spondisciy Snort.
Protection OF property and life from light
ming flashes has been subject that has
entralned the attention Of natural phioso-
pliers since Franklin sent up his historic
A,.e. The net result OF more than a century
OF attempts 10 secure protection has been
~ lightning rod In its more or less in
buildings of modern construction having
metaAic roofs aud often metallic frames as
vel are practically immune from attacks
BY lightning. The total number OF deaths
due to lightning In any given summer Is
comparatively very smnll-in the ratio OF
about one to each 100000 population IN the
United States.
lightning is exceedingly small, although
occasional fires are caused by 1t, especially
where gas pipek abound. Protection Of
electric circuits from lightning has been
an Interesting subject for research for a
number Of years and several highly efn'
cient devices have been constructed for
this purpose.
Today lightning Is little feared by the
station superintendent and should be very
little feared by any one. The time -honoTed
rule that II is wisest TO keep In the open
ana not seek the sheltsT OF trees is one
which common prudence dictates. Recourse
to the feather cd Of elg assessors, how
ever, Is no Longer necessary. except 70 quicl
ancient superstitiOns regarding handling
steel instruments and sitting In draushi