The Portland daily press. [volume] (Portland, Me.) 1862-1921, 1895-08-31
HABITS OF LIGHTNING.


been blown to pieces inside of buildings.
LII the winter of 1867 severe thunder
storm occurred on Niagara River and ex,
tended to Buffalo on the one hand and to
ST. GATHERINGS on the other. Terrific ex-
hibits of lightning flashes were frequent,
and the telegraph lines connecting the
localities mentioned were loaded beyond
the point Of safety to the operators. AS
night settled down upon the scene silent
lightning could be seen after every fash
streaming upwards from the tops of the
glass insulators. This exhibit ceased
with the succeeding fash These silent
discharges seemed to go from the earth
upward. The grand finale of the exhibit
ton was beautiful display of northern
lights, which the writer watched until
weary.
Mr.. Adde'S circular, already referred to-
mentions the fact that by Induction
blaze was started in the Hotel de Vile OF
Brussels, the spark Of induction setting
fire to a gas leak. The moral OF which is
to SO connect all metal pipe or rod stems
in some way together SO that the induc-
ton spark, which has an extremely high
voltage, will not have to jump, tbut will
go quietly along the highway thus pre-
pared for it.
An electrician living in a suburb of
Chicago relates that on one occasion. while
coming to the city in the morning as
usual, he saw bolt of lightning strike a
dwelling some blocks away. He was in
1,,% ha ON
that he felt an inductive effect from that
stroke Gases are not rare where during
heavy thunderstorm sparks snap across
the gap in an electrical gas-lighting cir
cult with very perceptible snap where
ground circuit is used, and the annunci-
ator drops in hotel, sometimes all go
off at once with rattling sort OF fire,
| like yolley from the awkward squad of
green regiment.
Now, when lightning has SO many char
acteristics and cratic ways, the question
comes briskly to the front, what are
we going to do abou9 its"
| There are two general forms of light
ming rods, which include all the known
species save the systems Of crank or
| two, whose ideas are closely allied to
those of Pindar's peddler. He said his
razors were not made to shave Without
to sell.
| 1. The Franklin rod a straight, often
single shaft, set up above the .highest
portion of the building, insulated from
the structure completely, and made up Of
sections Joined by loops-a chain with
very long links.
| 2. The plan patterned after the we'll
known rat-trap experiments cage in
which the structure is more or less in
closed. with many points projecting up
ward from all parts of the building. This
is known in france as Nelson's system.
| The network of wires is all connected
together by metallic wir es of goodly size,
and all are led to the earth, ground con-
portunity. 1.-THE ground contact. resistance
should be as near zero as possible.
Ground plates should be set up edgewise,
to contact with as many layers of earth
asEpossible. They should reach permanent
moisture, below frost. Ground contact
should not be made to the small gas pipes
in the building. Rods should not be in
sulated from the building. The i'm
munity from danger enjoyed in the larger
cities is mostly attributable to the preya-
lence of metal roofs, conductor pipes,
waterways, and other metallic conductors
leading to the ground. Preferably the rod
of iron or copper should be in the form
Of a ribbon-that is, the same amount OF
metal will better protect from adisruptive
discharge while having the same carrying
capacity for silent dissipation of a
charge The top Of the rod should be
pointed and tipped with some rust-proof
metal such as aluminium. Stick up min
iature rods until your premises bristles
with them. When you think you have
enough hunt place and put up one more
Make perfect. solid metallic contacts
everywhere.
Finally, if professional lightning-rod
man threatens to put in an appearance
and rod your premises take the great labor
leaders, advice: "Save your money and
buy a gun '-Chicago Tribune.