The Louisiana Democrat. [volume] (Alexandria, La.) 1845-1918, 1895-08-07
ALEXANDRIA La. WEDNESDAY, AUGUST Z 1895.
PRoTEcTioN FROM LIGHTNING.
The Utility of Safety Kods-some inter
estine Ststistics.

PROTECTION FROM LIGHTNING.
The Utility Of Safety Ro,is-somo inter
estins Statistics.
Lodge, one of the highest authori-
ties, has said that any conductor
lightning rod) is better than none,
although but few Of none of them
are absolute and complete safe
guards. Some form of lightning rod
is essential to anything like securi-
ty. Putting aside the question of
comparative chcapness of insurance
against lightning and the cost of
lightning rods, we can go at once to
the matter as to how much light
ming rods protect. In order to do
this, it is necessary to get an idea of
the nature of the action of lightning.
There exist all grades of lightning
discharges, from the steady strain"
or gentle flow, of the electric cur
rent, comparable to the flow of wa
ter in river with slow current, to
the 'ilnpulsive rush," Or intense
disruptiye electrical discharges of
high momentum, which are compa-
rable to an avalanche on a steep
mountain side or q great food.
Where the discharge is of the former
character, lightning rods do protect,
but in the latter case even the best
constructed conductors lose their
efficiency justas a safety gate in a
waterway would prove useless in
the rush of waters of a great flood.
It was such disruptive discharge
of lightning which caused the dam
age to the Washington monument
on June 5, 1885. There are many
flashes that are of an intensity which
the human body can readily with
stand.
lightning rods should be either of
copper tape weighing six ounces to
the foot or of iron rod or tape weigh
ing IS ounces to tho foot. The top
of the rod should consist of clusters
of points which have been plated tc
prevent corrosion or rust. The
grounding of the rod should be in
damp earth or running water, and
independent grounds are preferable
to water or gas main pipes. There
! is no definite area of protection de-
pending on the height of the rod
The risk of a lightning stroke is
about five times greater in the coun
try than in the city. In fact, it il
hardly necessary to place rods OF
the ordinary block dwelling house!
of the city.
The region of greatest frequency
of thunderstorms in the United
States is in the southeastern portion
extending from Georgia to Missis
sippi, where 40 storms occur eacl
year at tho average. In the north
ern part Of the United States no
moro than 20 occur, and on the New
England coast but 10. The summe,
time is the time of greatest frequen
cy. This occurs in May or June K
the west and southwest of the grea
lakes, but the time is retarded K
July and August, with progress to
ward the west, south and east O
this region. The general direction
of approach in the United States il
from the west, but in southern Flori
da they approach from the east, thu
following the direction of the gen
eral movement of the atmosphere.
About $50 people are killed an
nually by lightning in the Unitet
States. Of these casualties usual,
only one death occurs in each o
January, February, November ant
December; in March, 3; April, Is
May, %; June, n; July, SO; Au
gust, 4e; September, Is; October
IL. The annual loss by fire due t.
lightning strokes is estimated a
81, 500, 900. Of the annual numbe
of SIS buildings set on fire, $40 wer
barns, stables and granaries, 2
churches and 1871 dwellings, Nev
York Times.